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Troubleshooting your heart rate monitor/strap HR spikes

For those who train with heart rate monitors often, you probably know all too well know the tell-tale sign that your little device is lying to you about your heart rate.  It starts off fairly innocently with a gentle rise in heart rate (HR).  But before you know it your HR is blistering through the 150’s, 160’s, and right on through the 200bpm glass ceiling.  Sometimes you might even reach into the mid-200’s.

After you finish your activity and get back to your computer, you’ll probably see something like this – a major HR spike, followed by more normal HR activity:

Heart Rate Monitor Graph Spikes

Frustrated, you poke at your HR monitor some, perhaps browse the Internets a bit – but in general forget about it, until it happens again.

Well, let me help ya out and explain why and what it’s doing.  And…I can probably even help ya fix it too!

Proper Wearing Methodology:
Let’s first start with how to put the strap on.  As the most important thing to do is ensure you’re wearing it correctly.  On the Garmin ANT+ straps, you’ll want to ensure the Garmin logo is right-side up, and the electrode side of the strap is against your bare skin.  Which side is the electrode side?  Well, the side with the little bands, not the shiny side.  I’ve circled these in the pictures below:

Garmin Classic HR Strap:

Garmin Classic HR Strap Electrodes

Garmin Premium HR Strap (also called soft HR strap):

Garmin Premium HR Strap Electrodes

And for all you Polar folk, their coded HR strap:

Polar T31 Coded Strap

(Minor side note, as you may know, none of the Garmin ANT+ HR straps will read HR underwater more than an inch or two away from the watch, as I showed in my 310XT review while underwater.  However, the T31 coded straps from Polar will work underwater with their respective Polar units – just ensure it’s noted as T31 coded.  Also note that you cannot mix Polar HR straps/units with Garmin HR straps/units.)

Now, one last important item to note is that it goes UNDER your shirt against your skin.  It should not be worn over your clothing.  Also, the ANT+ folks note that from a placement standpoint “the strap is worn on the ribcage, below the pectoral muscles or breasts”.

All good and you’re still having issues?  Onto the next section we go…

The root of all issues:
So assuming that you’ve got it all correctly ‘installed’, let’s look at what typically causes the spike in HR (if it’s over 200bpm, it’s likely not legit unless you’re a seven year old).

1) No moisture, dry air: During the winter months the air is often fairly cold, and fairly dry.  This means that you’re less likely to have moist skin (due to even just skin perspiration), and even less likely to be generating any sweat right from the start of the workout.  This in turns lowers your conductivity ability from a readings perspective.  Which, means you often get incorrect readings.  Simply introducing any moisture at all will usually remedy the situation – at least until you begin sweating enough to let that do its job.  We’ll talk about moisture additives in the next section.

2) Synthetic shirts (quick dry/tech shirts): While all of us love not being suffocated in cotton shirts, an unfortunate side effect is that those synthetic shirts (normally called quick dry or ‘tech’ shirts) produce additional static electricity buildup that messes with the readings.  This is most common when your skin and air are both rather dry, and very little moisture is present.  In almost all cases, simply applying moisture will immediately resolve this issue.  You can try rubbing the strap or your shirt with an antistatic agent – the ANT+ folks recommend simply a bounce dryer sheet, as that can help in some cases.  As a side note, some of the Polar straps actually have an antistatic component built into them that helps to alleviate this problem to some degree.

3) Wind on the bike: One fairly common issue especially in the spring/fall when you’re wearing simple bike jerseys but the wind and lukewarm air temperature keeps you relatively dry, is that when you go down hills fast, or simply the wind hits the right way, you’ll get incorrect readings.  This is often caused when the wind funnels down the front of your bike jersey and either induces additional static buildup as noted before, or introduces false readings through vibrations.  I can’t count the number of times where it seemed my HR was directly correlated to how fast I was descending – despite the fact that I was working less.  In this case, your best bet is either getting more gel to increase conductivity, or simply twisting the HR strap around towards your side a bit – that usually resolves is for me.  I don’t recommend trying to lick the strap while descending at 40MPH…many things can go wrong there resulting in you licking the pavement instead.

4) Electrical Interference (powerlines, train lines, etc…): This isn’t typically reported on the Garmin’s, but more the case on the Polar’s.  The Polar’s use electromagnetic signals to send the data from the coded strap to the watch, which can be interfered with by high tension power lines.  The Garmin’s on the other hand use the 2.4Ghz frequency and don’t have the power line issues typically.

The fixes:
The good news here is that there are a ton of easy fixes that you can quickly try out to

1) Sweat: This first one is a bit obvious – but will explain why the problem often goes away after just a few minutes of activity.  Once you start sweating it introduces moisture which in turn improves conductivity.  This in turn makes the HR strap happy and you get better readings.  So basically…work harder. :)

2) Licking it: This is the simplest option – and quite honestly what I do 99% of the time.  I just give it a big lick.  By ‘it’, I mean the two sensor pads on the back of the strap.  This will usually ‘tide me over’ until I start sweating enough to keep everything all happy.  And don’t worry folks – a HUGE LONG thread on BT the other day confirms that everyone else does it too.  See, here’s my lick-job:

My awesome spit bubble on my Garmin HR Strap

3) Heart Rate Gel: If you suck at licking, then you can instead use electrode gel to improve conductivity.  This is what’s typically used in medical situations such as an EKG where you’re trying to get a better reading/conductivity.  I actually use the gel mostly during the winter because I’ve found that many times on easy runs I’ll never actually produce a sweat due to the cold, and thus after a short bit of time my lick-job (as noted above), will actually vaporize.  The HR gel is designed to last considerably longer on your skin/strap. This stuff is incredibly cheap, and the bottle will last you a long long time.  Here’s my bottle I bought two winters ago:

Electrode Gel for HR Monitors

You can pick it up usually as your local running store, or online for about $5-10.  P.S., one little tip for those cold winter days (I know, it’s getting warmer now though), is to stick it in a sunny window sill, that will make it nice and warm when you put it against your skin:

Making it nice and warm in the window

4) Changing the strap position: Depending on what may be causing your exact situation, one option is to simply change the position.  Try sliding the strap to the right, left, or up/down.  Some folks even wear it on their back with great success.  In fact, when I’m having a day with lots of issues descending on the bike and the HR being erratic – I’ll simply slide the strap around my side a bit, so the contact portions of the strap kinda straddle my chest and back.  Works perfectly!

5) Replacing the batteries: Finally, last but not least – sometimes it’s just the batteries getting old.  You can pickup the simple coin replacement battery at virtually any drugstore, and even most grocery stores these days.  It only takes a few seconds to open up the back door of the strap and swap out the battery.  I usually have at least one spare battery in my tri bag at all times, just in case.

Wrap Up
Hopefully this will help you get through those pesky heart rate reading errors and get on with your workout.  If you have any related tips to fixing strange HR readings, feel free to leave them below in the comments!

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383 Comments

  1. What an amazing coincidence: yesterday I performed a workout that resulted in a graph that is absolutely identical to the HR-graph you used in this post! And herewith, that peak got an explanation, and I can cancel my cardiologist’s appointment! Thanks for posting this on this exact date.

    • dimitris

      My Polar Bluetooth heart rate strap was transmitting ubnormal heart rate data to my trusty Nokia E71 and Sony smartphone (using sports tracker app) and now it s fixed ( after reading a comment in this section)(i believe i have the newer version of the strap, which is made of soft fabric, there are no hard plastic segments).

      I haven t used the strap for a certain period of time and now, when resting it showed 100-150 bpm and during exercise 200-250, obviously wrong. I made sure the two sections on the strap were wet and I even changed batteries, but nothing happened.

      After reading a comment, I threw the strap in the washing machine ( I have to say that I religiously kept the strap clean and followed Polar’s instructions when i was frequently using it- wash it with water and soap after every use and every 5 uses throw it in the washing machine).

      After the washing machine, the strap is working flawlessly! During the time that i was not using it, it was kept in a clean environment so i don’t understand how this happened. Anyhow, now it is in perfect shape.

      Thanks guys and Rainmaker!

  2. Nice one, I’ve had spiked graphs in the past, time to ge me some gel! Interestingly (or not!) my strap tends to slip down until I get warmed up as well?

  3. Yuck – I could never fathom licking my HR strap (I don’t love it THAT much). Despite periodic cleanings, I just can’t bring myself to do it. I usually just run my hand under some water (either from the sink at home or a water bottle) and rub the sensors with my hand. In a worst case without water available, I’ll lick my fingers and then touch the strap.

    Interesting note about turning the strap around your body – never tried that one, but I’ll be sure to the next time it happens.

  4. I usually have the opposite problems, I have these huge dips, into my resting zone HR ,while busting my butt on the treadmill, swimming or biking. At first I thought it was a battery issue but that only fixed it temporarily.
    It seems to happen most while swimming which annoys me because I want an accurate calorie burn number, and I know that I burn more than 200 calories in 1hr of swimming at a moderate-fast pace!

    • Alan Taylor Farnes

      Yeah my wahoo hrm is doing that right now. It will get stuck on a pretty low number like 120 and just stay there. Could be that I’m not sweating enough or maybe need to replace the battery but it is really annoying.

    • werty

      Get a comprehensive blood test done for heavy metals. Get the whole panel. You are likely sweating out the uranium, thorium, lithium etc which is widespread in environment and shirts out these monitors and also causes major hair loss.

    • Javano

      Same here! For me, a 10 minute all out climb normally would result in about 180bpm average. For a while now my tickr has been giving me hugely inaccurate readings but always on the lower side. The other day, mentioned climb, again all out, resulted in sometimes 120, sometimes 90, sometimes 150… I’ve done the climb about a 100 times now so I’ve got a pretty good idea of what effort I’m putting in. Besides, I’m riding in humid, hot conditions so i’m soaked in sweat.

      I’ve got a race coming up where I would like to be able to pace myself from my HRM readings. I’ve tried most of the above troubleshooting except for moving the strap to the side or back! I’ll try that next time.

  5. Anonymous

    Coincidental.. Was having this problem with my garmin the other day!

    Is there any way to alter your stats after to get rid of those sectors, and maybe replace them with something more realistic? Kind of messes around with your stats for the whole session

  6. Anonymous

    I have the reverse problem. After my shirt gets wet with sweat, I start getting very high and erratic readings with the Garmin soft strap. There’s lots on this on the Garmin forums, but no solution!

  7. i simply squirt a few shots from my water bottle before i go and it does the trick

  8. Amy

    Thank you for very publicly admitting that you lick your HRM strap! I too am a licker. I think saliva is a better conductor than plain water. I don’t know this for sure, but it’s certainly easier and often more convenient.

  9. i always thought wetting the sensors as referenced in the manual referred to increased connectivity between the garmin unit and the hrm. thanks for the post, excited about more accurate HR readings at the beginning of my workouts.

  10. So, maybe you’ve got some insight into this part of the equation, which I have long wondered:

    How does the presence and amount of Chest Hair effect the HRM readings?

    I mean, I’ll be honest, I’m a groomer, which means my legs are like those of a prepubescent girl, and I tend to keep the hair on the rest of my body fairly short. But if I don’t whip out the Wahl for a bit, my chest hair becomes a luxurious forest, complete with it’s own biology.

    Granted, I haven’t thought to plot my Heart Rate results with my Chest Hair levels to come up with a solid theory.

    So, any thoughts?

    • Phil

      In short (being a hairy bugger) I have to shave my chest for my (new) Zephyr HxM Smart to work – at all. I know this is an old thread but as I was unable to find any conclusive answer for myself I went ahead and shaved and hey presto! I do have a beating heart after all…

    • dave-o

      I’m a very hairy guy. I’ve found that by trimming the chest hair just underneath where I put the electrodes makes a huge difference. Sadly, I also swim so I end up looking like a total weirdo with these two shaved strips on my chest. Do those monitor/watches that use your wrist and don’t require a chest strap actually work?

    • It depends a bit on the company and the sensor used. I’ve reviewed almost all of them here though, so you can poke around at some of the more common ones like Mio Link/Fuse/Alpha, Adidas Smart Run, and the TomTom Cardio lineup.

  11. Great post Ray. I’ve been having this exact issue with my 310XT and wasn’t sure what to do about it. With my Polar S725X, either I got HR readings or I did not. There wasn’t a middle ground. Can’t wait to try some of these ideas, although the germaphobe in me isn’t too sure about the licking technique. :( Thanks again!

  12. Hey Gary!

    Hmm, I’m not sure on the chest hair thing and how it might affect it. For better or worse, I don’t end up like a fuzzy bear. Perhaps someone else might know.

    Sorry, but thanks for dropping by!

  13. Great post. I go through that almost every workout even though I drown the contact areas in water before putting it on my chest. I think I’ll get some of that gel & see if that helps.

  14. I bought the gel you linked to in your post and tried it for the first time this morning. It worked awesome! My heart rate graph was beautiful. No bogus spikes whatsoever. I’m sure these guys have seen a “Buh-Bump” in sales since your post (sorry couldn’t resist). Love your blog! Keep up the great work.

  15. You wrote: I’ll simply slide the strap around my side a bit, so the contact portions of the strap kinda straddle my chest and back.

    Can you please make photo how exactly you wear it?

    I bought electrode gel (work great at start), i bought anti-stat spray, so fixed almost all spikes, except downhills against strong wind on my road bike! :) Tried to move strap to the side, but just a little. Tried also move strap on my back, but it worked only before ride with freshly electrode gel added .. then in training after downhill spike i stopped and moved strap on my back, but it did not work, i mean i get no HR data at all.

  16. you said: I’ll simply slide the strap around my side a bit, so the contact portions of the strap kinda straddle my chest and back. Works perfectly!

    Can you make a photo how exactly you have strap fitted, on left side i guess?

    I use electrode gel, anti static spray and still have few spikes when descending againts strong wind on my road bike.

    By the way would not help to stick something to strap from outside between strap and jersey (shirt)? but im not electrician, but i guess some shield would help.

  17. Hi Karel-

    I’ve uploaded a photo of wearing it slightly to the side, on the 310XT Product Review page I did, in the gallery at the bottom of the post (right before the comments section). Just click on that gallery and then check out the last picture in the series. Hope this helps!

    link to dcrainmaker.com

  18. I’ve been having this problem with my Garmin 310XT HRM except it gets worse as the run (or bike ride) progresses. It behaves normally for the first 15mins or so and then heads up to 200-240bpm numbers. It seems to get worse as I get more sweaty and electrode gel makes no difference. Moving the strap can fix it for a couple of minutes and then it heads straight back up to the silly numbers. It’s behaving the same for my husband and I know that my HR is not as high as the HRM is telling me.

    It’s not even 6 months old and this started happening after 2-3 months and is at the point where I don’t even bother using the thing. I’ve read others having a similar problem to me and they have connected the GArmin HR sensor to the Polar wearlink strap and that has fixed the issue.

    Do you have any insight into this problem?

    • Eddie

      I have the same problem with both my garmin and sportline monitors also my roommates garmin. starts normal then HR alternates between 200-250 and 50-70 in a sweat soaked cotton shirt about 30 minutes in. both for recovery rides (HR 115-125) and LT intervals (HR 157-162) Useless or is my heart just jacked (was told once I might have a heart murmur) also am a regular mmj smoker with some phlegm in my lungs could that be clicking around making vibrations? sometimes on the bike or running it seems like my cadence gets added to my HR reading. Also I’m a diesel resting HR: 37 max HR: 178 biking, 183 running. 30yo triathlete and cyclocrosser

  19. Hi Os-

    Given it sounds like you’ve tried everything, I’d suggest contacting Garmin Support. I know that there were some early batches of 310XT units with HR straps that they are replacing the HR straps on, without any charge. A quick ring to Garmin support may help you out.

    Sorry!

  20. I have a 310XT and used to get the same HR spikes, when the strap was dry or TOO wet. The solution for me is ECG contact gel (the same as licking the strap except it doesn’t dry as easily), but the real solution was to buy a Polar Wearlink strap without the transmitter and use the Garmin transmitter instead, it fits neatly. Has worked perfectly so far.

  21. Nicolai Bentsen

    I resolved the spike problem with a Garmin Classic Heart Rate Monitor today – which should be compatible with most Garmin devices.

    After 12 months of heart rate spikes with the Garmin Forerunner 310XT and it’s soft strap I bought a Classic Heart Rate Monitor which is not as comfortable, but a lot more resistant to static electricity.

    When using the Garmin Premium/Soft strap that comes with the 310XT it generated so much static electricity against my clothes that I got a zap every 200 m when I discharge (when touching the HR monitor on the treadmill). But after I switched to the Classic Heart Rate Monitor I didn’t get a zap even after 8000 m.

    So with the new HR monitor I was finally able to monitor my run accurately since I bought the very expensive 310XT..

    Garmin knew about the problem when I contacted their support and offered to switch, but that included being without my HR monitor for 1-2 weeks which is why I simply bought a new one from Amazon instead.

  22. I too have had problem with the Garmin soft strap, far into a run when the shirt gets very wet. I tried all of the usual things including a different shirt, electrodgel, new battery and it didn’t work. Contacted Garmin and got a replacement – same problem again. Now I will try a Polar Wearlink+ strap with the garmin transmitter and see if that helps. It seems lots of people are having problems with the soft strap, and since most problems come at the end of workouts it isn’t the normal lack or contact or static electricity problem that is covered in this acticle. Would be nice if DC Rainmaker could push Garmin to comment on the problem that their product has.

  23. Anonymous

    Great article. Thanks!

  24. Anonymous

    Very helpful article. Thank you!

    This is the first time I’ve found documentation that precisely mirrors what I’ve experienced.

    At first I thought I needed to see a doctor. But when I started seeing readings in the 240s at times when I wasn’t exerting myself and felt fine I realized there was an equipment problem.

    In my case, I’d only see this happen on relatively cool days, wearing a “keep you dry” bike shirt and when turning into a strong wind.

    Thanks again!

  25. I recently contacted Garmin, and they suggested that I CLEAN the heart rate strap. They referred me to the instruction manual, and sure enough, it says to clean the strap after every use… and after every 5 uses, use dish soap.

    The strap looked clean, but here is what I did. I wore it sitting in front of my computer, and around the house. HR 175 – 250. Yeah Right. Then, I cleaned it as suggested, and did a workout. Even wore a technical shirt. I’ll be damned. The thing gave perfect readings the whole time!! Two workouts under the belt now, with good readings. Let your users know!

  26. Beau

    After many random heart rate spikes, odd performances and general issues with my heart rate graphs, it finally got to a point where every workout started in the 250 bpm range and within 2 mins it was fine. I decided it was time to replace the battery….

    So I TRIED to replace the battery which made it no longer work period.

    After some searching, someone recommended putting the battery in backwards to short-circuit the HRM. This did the trick! So if you are having weird graphs – as some do in the comments above…short circuit then replace your battery!

  27. Anonymous

    Hi Rainmaker,

    Please could you advise me on the following matter: I would like to use a heart rate monitor watch with a chest strap in the winter however I have an old Polar watch and my strap is not working (the watch do not receives any signal) under a shirt and/or thin jacket (not even under a sigle very thin T-shirt). What do you think, is a Garmin working under a shirt and a thin jacket
    (is the technology different) or should I forget to count calories and zones in a cold winter outside? I am considering to buy a Garming Forerunner 305, it would be fun to see all (motivational) data. (Unfortunately I have a lot of overweight and I can only walk so I need to have a jacket on mee). Thanks a lot in advance for any advice! Peter

  28. All of the above solutions worked for me when I was using a Polar S720i, but with my Garmin 310XT and soft strap, I am still having problems. I have been training indoors all winter, where it is neither cold nor dry, and I am pouring with sweat not long into my workout, and I still get erratic readings until well into the session. For the first 3 months of ownership it worked fine, but now I have these problems every time I use it.

  29. Anonymous

    Bingo – my symptoms met your cure, in my case, cheap electrode gel stopped the dry contacts issue.

    Many thanks, –Pete

  30. Ray, any word on when the new-new premium soft strap is going to be available for stand-alone purchase, if ever? I’m a 310xt user, and I’m now on my 2nd polar Wearlink+ strap, which seems to last a little longer than the original Garmin soft strap, but still has problems of its own.
    Do you think they will ever offer the new strap standalone without the transmitter? Based on their offering for the existing soft strap (strap+transmitter together as the only option) I’m guessing not.
    If not offered soon, I’m thinking about just going back to the old plastic strap, but if I’m going to buy a whole new strap/transmitter, I’d rather it be the newest one.

  31. Hi Chris-

    Yes, they’ve been offering the standalone strap since back in January. Any ‘premium strap’ bought off of Garmin.com will ship the newest 2010 version. And the majority of straps bought off of Amazon will (just look for the product ID number to end in: -02).

    Enjoy!

  32. Hi Ray, I have read your article, and I keep getting false data on my 310. My graph is just a bit different. The peaks above 100% max, is placed in the middle of the trainings session, instead of only the beginning.

    Example.
    1 km = 103 % max
    2 km = 111 % max
    3 km = 116 % max
    4 km = 91 % max
    5 km = 94 % max

    Im pouring water on the strap before I put it on my chest. And I place it as you describe.

    Do you have any ideas ?

    Best regards,

    Anders, Denmark, Europe

  33. My wife and I have been experiencing similar problems to the ones described. We both have the Garmin premium strap and have been using them for a year or so. After buying gel, wetting the contacts and reading a lot of ideas, nothing seemed to be helping. I was about to give up and try a different strap when I stumbled upon a solution. I believe that the electrical connection that is made by BOTH snaps is important. Like most people, I always unsnap the HRM on the same side every time, and had never unsnapped the other side. So I unsnapped and resnapped the unused side 20 times or so, and have had zero problems since then. My wife has had the same results with her strap. No more gel, and I haven’t even been wetting the contacts before I go. Hope this helps someone.

    • Tania FitzGerald

      That really helped! My heart rate monitor kept currint out – fixed it with gel for a few days, but after reading your post, unsnapped and snapped the monitor and I am off again! Thank you!

    • Edwin Knepshield

      Well your snap idea got me to thinking that “corrosion” might be building up in the snap on the strap (pardon the rhyme), I took a small paring knife and carefully scraped the surfaces in the strap snap. Eureka! It’s been working now for 5 minutes straight. I may have to add this to my training regimen.

  34. Try this: Link your wrists with a pair of anti-static straps used by electronic and computer repair techs antistatic strap . You can find them at electronics stores eg StarTech. Buy two, connect them end-to-end, put one on each wrist, and although my testing has not been exhaustive, I think you will see a disappearance of the high heart rate in the first minutes of your run and the elimination of heart rate bursts later in your sessions.

  35. I can’t get the screws out of the battery box on the premium heart strap. The other hear rate strap I ended up stripping with a coin. Why is this so hard to get the battery out?

    The screws are beyond small.

  36. Gideon

    I actually seem to have the inverse problem. After 30 – 1 hour, my Suunto HRM starts to wander – either hiking slowly to the 220’s, or stabilizing around some 150 – no matter the terrain or the effort. I ride in warm weather and sweat profusely – my synthetic shirt is soaked – so it is not a dryness problem – I even thought the shirt could be electrically shorting the sensors(?) – it seems to start often after some strenuous portion – where my breathing may get less cadenced – I thought the R-R measurement may be screwing up the values – but the log does not show that… Suunto replaced the strap (not including the transmitter) – no improvement..

  37. Thanks a lot for posting this. I’ve had this happen numerous times, and it’s been much more frequently as of late. After reading your article it makes perfect sense. It’s getting colder, I’ve been doing more rides early, when it’s REALLY cold, and I’m definitely not working up a sweat early on, cause the first couple of miles are flat or slightly downhill.
    I never experience this running, due to the fact(from your explanation) that I sweat like a pig, even during easy runs.

    I’m glad I read this, I was worried that my Garmin was starting to die on me. Glad to know of these solutions.

  38. Anonymous

    can you wear the heart rate monitor on your thighs? Wearing it on the chest is very uncomfortable
    ?
    thanks

  39. “can you wear the heart rate monitor on your thighs?”

    I think not. I believe the HR strap picks up the electrical impulses from the heart that trigger heart beats rather than the actual beat or pulse. To confirm, try it on your thigh and see if you get a reading.

  40. As well as the spikes, I get a similar issue to gideons on longer rides. Usually after really pushing it my reading drops and stays at some really low value. Any ideas why this might happen ?

  41. Great post, DC. Thank you. We get questions about high, wacko readings on occasion in our heart rate training group at RunningAhead. I think I’ll make a permanent link to this. Keep going!

  42. Anonymous

    To add to the comment #33 by Greg:
    I also own a Garmin PREMIUM HRM STRAP. My legacy Polar strap always works flawlessly. After three months of use, the newer Garmin PREMIUM started to give me erratic mid-workout readings. After having eliminated all the rest (wetting the electrodes with salty water, varying the position of the strap, wetting the t-shirt to remove statics, resetting the transmitter by removing the battery, all to no avail), the only thing that worked for me was:

    anti-scratch electrical contact cleaner.

    You can find it in any hardware store, it is a silicone grease spray that cleans, desoxidizes and protects all kind of electrical contacts. Usually applied to automotive contacts and hi-fi appliances.
    If all other solutions fail, try this one, and enjoy the run!
    Alex, France

    • Andrew

      What kind of issues were you having. I’m having my drop to 1/2 of my actual HR after I’m well into a workout, similar to what you mentioned.

    • Cath

      I too am getting the same issue, when I’m a few km into a run my HR apparently drops to between 100-130 (curious since it is normally above 180 during running). Sometimes after I stop it goes back up to 180+, so something definitely isn’t reading correctly. I haven’t had any spikes, only dropouts in my graphs.

      I thought it might actually be something to do with interference from the sports bra or something – any other ladies having bra/strap compatibility issues??

  43. Anonymous

    Just to confirm: apply the electrical contact cleaner onto both snaps (white metal parts), not onto the black electrodes!

    Alex, France

  44. I have this problem a lot when running in cold weather. Instead of heart rate gel, I tried aloe vera gel and it worked like a charm.

  45. yano

    Ray!
    I was just ready to smash my Timex HR soft strap to the wall when I came across your post …
    Thanks to your ECG gel hint you’ve made me save 50 bucks and a lot of angry! :)
    Long Live to Ray (and to his precious posts) ! :)

  46. Anonymous

    Thanks my friend, very informative

  47. jeffcaw

    thanks a ton for this informative post… downhill 36 mph and a 240 heart rate. your explanation was right on.

  48. Kevin

    I was having problems with my Garmin Premium HR strap. I read this post and the comments and tried everything except buying the gel. I considered adding “one more thing” to my list of items I need on a ride/training to be a last resort.

    However, desperate, today I had a breakthrough. I took off the snapped-in sensor and completely wet the fabric strap. I wrung it out the best I could and then strapped it on and put he sensor in place. This worked for me like a champ. I don’t know if the synthetic fabric the strap is made of was interfering with a charge of its own or it was the soaking that finally made the right contact, but this has solved my issues completely. Hopefully just one more success story for troubleshooting to share.

  49. Today I found one of sources of mysterious HR spikes during running. I wear a Fixx Road ID (dog tag style)which would come into contact with my chest strap. Once I removed the tag, my HRM functioned normally.

  50. Anonymous

    A bit off topic, but can one mix and match HRM straps w/monitors as long as they are of the same brand?

    I need to have the battery replaced and I was hoping to use another (both Polar) in the meantime…

  51. Anonymous

    Does wearing a sports bra with an underwire cause problems with heart rate showing up or being incorrect?

  52. Anonymous

    Are all chest band the same, not transmitter onley the soft strap. Looks like Wahoo, Polar and garmin uses the same type of alastic strap, but it it possibel to mix eg. Wahoo transmitter on polar strap ?

  53. Most of the ANT+ ones are the same, but the Polar straps are different (different material, texture, etc…). But the Wahoo, Garmin, Timex, Cycleops, _____ (fill in the blank ANT+ vendor) all use the same OEM behind the scenes.

  54. Dos that mean that Wahoo Blue HR also can use the Polar Wearlink strap ?
    I assume that the elastic strap onley contains a sensor and all the differens is in the transmitter ?

  55. Yup, correct, no problem at all (I’ve tried it). They all mix and match. Enjoy!

  56. Does anyone know if it’s possible to wear a Garmin Ant+ HR strap at the same time as a Polar Wearlink Strap (5khz coded)? Wondering if either would interfere with the other. I like the polar for fitness features, but want to capture data to use with Sports Tracks software, which can’t use Polar live.
    I believe Ant+ is 2.4Mhz, so I’m hoping there would be no interference.
    Thanks,
    Michael

  57. Like several other posters, my problem starts mid run, usually around 20 minutes in. I will be at 170~ bpm, and then notice a gradual decline. Everytime I look down it will be slightly lower… 165… 160… 155… and it just continues to taper off until I finish the run. If I go long enough it will get down in to the 70’s. I almost get the feeling that instead of actually tracking my hr, it’s averaging my heartrate but registering 0 for the second half of the run, and constantly averaging the increasing amout of time at “0” with the earlier rate of 170. But I can’t find anything that would explain this behavior…

    By the way, this is a new unit. I’ve only had it a few weeks.

    • Llewis

      No Name
      I’m having the same issue. Everything starts out fine and about mid-run I get the gradual HR decline. Did you find anything that helped?

    • Sergio

      Hi, I’m too having the same problem, have been using the Garmin Premium HR strap for a year no with my 620 and experienced the exact problem on my last run, I changed the battery but it didn’t help, tried unpairing the sensor to pair it again and now it wont even be recognized by the watch. In fact the connection was lost midrun and the watch started reading 0 bpm for the remaining of the activity. What to do?!

    • biastee

      Have u tried transfering the sensor (transmitter) to a known good soft strap?

  58. I just wanted to add my experience as one of those people who have a problem with the HR reading artificially low numbers. It starts out seemingly ok, but after 20 minutes or so the reading will drop down to 100 or below, even though I’m maintaining a similar effort as before. This happens with both the old stiff strap, and a new soft strap. I have tried it on my back (even worse), wrapped around my side (about as bad), and I have used the giant tube of electrode gel (no apparent effect). It seems I’m unmonitorable. Is there any common thread among us getting the low heart rate readings? I tend to be a heavy sweater, I’m not sure what else would be relevant.

  59. Anonymous

    After trying all the tricks found here and other places, my solution to the heart rate strap problem is to return it for a new one. Each time I have done this, the new strap works for about 45-50 days before it starts some sort of shenanigans. I use the strap at least 14 hours per week. When the errors start I just return it again.
    Garmin needs to figure this one out and I do not need to be purchasing 7-8 straps a year.

    • Esterhase

      I’ve had the exact same experience, but with Polar products. Tried everything, and i’ve been struggling with them for about ten years. The straps always start to give trouble after a few months, and none of the fixes (clean, tight, gel, etc.) seem to help long term. I was hoping there was something better on the market, but doesn’t look that way.

  60. I have tried every trick here plus trying the Polar Wearlink strap which will allow the Garmin monitor to snap on. I find that whilst the Garmin soft strap will spike irrespective of any fix you can think of, the Polar drops out and is totally unresponsive if I don’t rinse and completely dry between uses. Additionally as others have mentioned, all the straps seem to behave reasonably ok for a month or so then become problematic.
    Dom

  61. Anonymous

    Thanks! I’m new to the tracking life, and this article was so informative and consolidated what I needed. Hardly anything like it out there.

  62. Oh my, I feel so silly… I thought the small black metal things right under the snaps (soft strap) were the electrodes, and I was looking for solutions because that part was not touching my skin (I have a slightly sunken chest)… Now I realize it is not such a bad design after all. Thanks for switching the lights on in my brain! Now if only I could find a good software to display my HR on the computer… I got Golden Cheetah and ANTHRM to work, but still looking for something “nicer”.

  63. Can a single heart rate strap pair with two different monitor units simultaneously, say an FR 70 and an Edge 500, for use in a triathlon or the like?

  64. Yup, no problems at all – I do it all the time, especially for testing. Will probably actually do it in a little bit here for a few tests.

  65. Anonymous

    This is a great post, thank you! I know this is a big delayed, but do you have any insights for the folks who experience the drastic dip in HR after about 30 minutes of activity? This is my current problem and driving me nuts. It consistently displays down to 35-40 bpm after 30 minutes, which is frustrating to see. Any thoughts? Could it be moisture getting into the battery? Or is there a way to clean the battery connections?? Any thoughts would be appreciated. Thanks!!

  66. Anonymous

    Add me as one more that has had lots of problems with the Garmin premium HR strap. The last one lasted me only 3 months (I tried everything.) The old style lasted me longer so that’s what I bought to replace the last premium garmin. The other thing I like about the classic is that all the electronics are in a plastic band which is easy to clean, whereas on the soft-strap you have contacts (decreased reliability) and wires/contacts on a soft-strap that you’re not allowed to wash. With the classic strap I throw the elastic in the washer and it’s cheap to replace when you need to (unlike the premium soft-strap)

  67. Anonymous

    Hi Dc rainmaker, I saw your post about heart rate spike. How about gaps between the heart rate? here’s a pic to clearly illustrate what i mean. link to fbcdn-sphotos-d-a.akamaihd.net

  68. Had the same problem, on both mine and the girlfriends heart rate monitors. Solved by soaking the straps in water and some mild dishwashing soap over night.
    As you sweats, the salts in the sweat is fairly hard to wash out of the belt with regular water. The soap will do the job.
    Good luck :O)

  69. Anonymous

    I solved my problem of low readings for the soft Garmin heart rate monitor by placing it above my nipples and not below.. worked perfectly for a 45 minutes run outside. I’ll try this out again on a longer run this weekend.

  70. I used to get this problem for almost every ride. I used three different chest straps and monitors, and several different jerseys. It seemed to be more related to the jerseys, though not totally predictable. But when I bought an Endomondo jersey I got it at the start of every ride, with any type of strap and monitor.

    Then about a year ago I started adding a Lenor tumble drier antistatic sheet to my stuff after every wash. Since then I’ve never had a single spike with any kit at all.

    But, not all tumble drier sheets work as well. I tried the Tesco brand, and the spikes came back. So I went back to Lenor and they disappeared again.

    Cheers, Alan.

  71. Kuota Grant

    I’m writing is to offer up a hint as to getting better contact with your HR Strap. Here’s what I’ve found to work pretty well. And, not judging, it’s generally more pleasant than licking the strap. But I digress.

    After applying chamois cream to my junk I do a light rinse of my hand with water and schmear the chamois / water mixture on my chest, right where the HR contacts would be. Then I wet the HR strap contacts under the tap and finally “strap on”.

    I’ve yet to have any idiosyncratic BPM irregularities using this technique. It seems to work with Assos and Chamois Butter. Let me know if it works for you.

  72. Rainmaker,

    I’ve been having problems with the Garmin Premium Heart Rate Monitor Strap (Soft Strap) with my 910xt. It seems to drop the bpm reading every now and then, no matter how sweaty I am. I thought it was the strap, so I called Garmin and they sent me a new one. I used the new strap with my old monitor for several weeks and everything was back to normal. But now the new strap is having the same problem. So as a test, I tried using my PolarWearlink monitor with my Garmin soft strap, and it worked fine (you can tell it’s consistently on, because it makes a ticking sound when it’s connected). Has this problem happened before? Any guidance? I am really at my wit’s end!

    Thanks for any help!
    -Andrew

  73. Fido

    Initially my Garmin 305 HRM worked very well; it could, in fact, give hospital equipment a run for its money. However, over a period of time I started getting erratic readings and then it faded altogether. After some back and forth with Garmin, they agreed that they would look into the problem (it being in the warranty period).

    Just before sending it of, as an experiment I decided to put the strap on upside down – and it started working as of old! Yes, upside down – not back to front! Now the Garmin logo is the wrong way up when I wear it, but the readings are fine. Garmin has said that there should be no problem wearing it like that. Go figure!

  74. My wife had major issues, which we tried everything to fix, including swapping straps (used two version of polar, and the garmin one), conductive gel (she’s a physiotherapist, so we have gallons of the stuff). Nothing worked.

    Then we moved the strap to above the breast, and perfect now.

  75. Manuel K

    Had the same trouble with peaks. Followed your advice and swaped strap to Polar WearLink. It works perfectly!!! Thanks very much Ray for the post – you save me lots of time correcting wrong HR data.

    Manuel from Germany

  76. I recently had some cramping around my heart rate monitor during a Half Ironman, so took it off mid run and put it into my Spi-Belt. When i uploaded the data, voila, i had a heart rate the whole time…after i took it off…the heart rate was very similar to my foot cadence….i think for those that are getting readings in the160- 200 range that don’t think they should, it could be too loose and measuring your body’s up/down motion instead of your heart beat. Here’s my data…notice it went from 140ish to 160s steady(i tend to have a slow cadence in the 90 degree weather)
    link to connect.garmin.com

    In terms of cleaning it….i wear it into the shower every once in a while and it seems to do the trick for cleaning…

  77. Steve Taylor

    I’ve been having a lot of problems recently, leading to a graph almost exactly like the one above, with ridiculous HR reading during the first 6-8 minutes of my warm-up on the treadmill. I’ve tried changing HRMs/straps/monitors, using spit/salt water/ECG gel. Nothing seems to make any difference.

    After reading this article it has suddenly clicked that the start of the problem coincides with my gym changing to new treadmills. I’m getting static shocks when I touch the control panel. It appears I’m running on a van de graaff generator.

  78. Les R

    I just got my first “Garmin premium HRM” and so far it is working well. I see in the manual (yes I’m one of those crazy people that reads the manual) it says to unsnap the HRM from the strap when not in use. I’m not sure if this means after each run or if it’s not going to be in use for an extended period. I’m concerned about damaging the snaps (on either the strap or the HRM unit) if they are are used so often (off and on each day).

    Any thoughts on this?

    Thanks,
    Les

  79. JJ

    I replaced my Polar FT60 with a Timex Run Trainer about 2 weeks ago. HRM was working fine most of the time but on a walk recently I had spikes. I think it was due to dryness and the fact that the strap was not tight enough. Made sure to retighten strap after each use and that helps. Yesterday morning after an hour on my stationary bike, my rate started to spike into the 170 to 190 range (usually my HR maxes out at 160 tops). I sweat heavily and I am wondering if too much moisture causes problems. I had small spikes today after I got off the bike and was stretching. When I stood still, my HR went back to normal. Has any one used the timex transmitter with a strap from another manufacturer successfully? Should I wash my strap with soap?

  80. Ron

    Question I have a Garmin edge 800. THere seems to be a lot of variation in calories burned between and my friends riding. I just purchase a Polar RS300X heart rate monitor watch with the wearlink 31+ chest strap. Could I wear the polar chest strap and my Garmin Edge 800 work with it? I want to compare my watch to edge 800 calories burned.

    Thanks

  81. Max

    Could you use something like Vaseline as a gel for your heart rate strap?

  82. NorthernVirginia

    Finally, an answer to a serious concern. I have an implanted defibrillator and have been shocked by it from running too hard. My heart rate went way up and BAM! So I started using a Sportsline monitor. It started giving me huge leaps in bpm, from about 120 to 180 and climbing. That really worried me and I contacted my doctor (no help there) and the manufacturer of the monitor and the defibrillator. They had not heard of the problem. The last thing I wanted is for it it be accurate, that my heart rate really was surging. This gives me some confidence.

  83. Nottingham UK

    Really helpful advice. I have a Polar and whenever I go downhill on my bike at hit anything over 25mph my max heart rate leaps to 200+ only to settle back to the normal rate once I am on the flat. I am thinking of wrapping bubble wrap round the monitor to protect it from wind chill. No one has thought of THAT!!! Followed the advice and bought a bottle of gel through Amazon. Amazingly cheap and very effective.

  84. Pop - Australia

    I have a Polar FT80. When I wear an acrylic shirt, the heart rate jumps to around 160 as soon as I start running. It stays like this for about 10 to 20 minutes. After reading this blog, I changed my shirt to a cotton polo shirt. Got a good result straight away with a proper reading. The resulting graph was smoother and there were no spikes. The shirt was the only thing I changed. Same wetting procedure and same wearing location. No gel.
    Thank you for helping me solve my problem.

  85. Banjo Paterson

    Hi DC – I know this is an old thread, but got a super high readout at the beginning of my run today (200-220 Yikes!), adjusted strap, waited for sweat — nothing. Then unclipped the HRM from the strap (whilst running, too) and put it back on and whoa-la, normal readings. Not sure what happened between the HRM and my 610, but whatever it was that seemed to fix it.

  86. Lampros

    Hi DC,
    The erratic readings have mainly 3 reasons.
    1.Not wet enough sensor. Solution–apply gel.
    2.Static electricity (this is to blame for spikes during startup). Has to do with atmosphere condition, clothing ( mainly synthetic). Solutions–Try to discharge yourself, just before your workout, by touching ground, choose your clothing (try to find which of your cloths create the problem)
    3. End of battery life– get a new one silly!!!
    just my 2c

  87. my HRM problem was that I would get intermittent signal. it would work fine for 30 seconds, a minute, whatever, then nothing. Sometimes it would start up on its own or immediately if I touched my finger to the electrode area. I simply moved the contacts to the left so that one is over the base of the heart and the other one is on my side and have had no loss of signal now for 15 minutes. thanks a lot

  88. Andre

    I got my soft strap with Garmin 500 and was having all those problems. Garmin screwed up the design, that’s it. Bought the old Garmin strap and it has been working great for 18 months. Changed battery once when reading started to be irregular. Buy the old one for $37 at amazon and stop having problems.

  89. John

    I just pee on mine. Then I don’t have to lick, the salts and minerals conduct, and it is warm to boot!

  90. BillM

    I have chest hair and been having problems with the Garmin Premium Heart Rate Monitor Strap (Soft Strap) with my 910xt. I also had problems with a Timex strap I used to use on another watch. Commion problem is that until I build up a sweat the readings are of little use and the strap can slide down a bit too so that I end up having to pull the damn thing back up a few times. I’m sure some of the public think I must be wearing some sort of a bra but with a beard they must be a bit puzzled. I will try the Gel as licking drys too quickly, however I think the manufacturers should consider adding some small pimples to their electrode contact surfaces. These pimples would nudge their way through hairs and get a skin contact in a faster time than the flat surface.

  91. Steve Drew

    Hi, I happened to have a polar HRM strap, just swapped out the sensor w/ my Garmin, and my HR fluctuations were immediately resolved. Thanks so much for the very helpful article.

  92. Hi, I ran a loop twice. Its hilly and makes you work hard. But, I got two very different heart rate readings. On the second (erroneous) run, I improved my time considerably, and expected to see a bit higher heart rate, but instead I have peaks at 240-250 and of 210 at various points in the run.

    See comparison pic at: link to plus.google.com

    On both runs I wore shirts that were made of Polartec Power Dry material. The only two differences I can think of are (1) it was windy while running the second time maybe gusts over 20-25 Mph, (2) The shirt on the second run was thinner material so it would contact the skin more.

    Given the comments on static, is that what I am seeing?

    • Ray Maker

      Wind tends to dry out the fabric much quicker, thus decreasing the moisture available. It looks like in those sections, you didn’t get good connectivity. Sometimes on cycling, you’ll see issues at higher speeds (i.e. 30-40MPH) with wind and loose fitting jersey’s causing super-high HR’s like you noted.

  93. Bill Coffelt

    Has anyone tried the Garmin HRM3 heart rate monitor and strap? I have 3 Garmin HRM2 heart rate monitors, two Polar monitors and several Garmin and Polar straps. Two of the Garmins haven’t worked for quite some time and the last one stopped working today. Changing the battery and extra cleaning the strap didn’t help at first, but I did get it going again. I have been looking at strapless monitors, but I feel I might be trading one problem for another. Also, I am not sure there would be any that are compatible with my Garmin 310XT. So, I came across the HRM3, which apparently was just released and I ordered just the strap on Amazon.

  94. cat

    Can anyone adress the opposite? My Polar hrm seems to measure too low..

  95. ave

    The quickest fix is to have a close fitting jersey. End of story. :)

  96. My Garmin Edge will also pick up other HR monitor straps on some days, skewing my readings..

    • Ray Maker

      Assuming you’ve paired it once to your strap, it will only ever connect to your own strap. It’s possible however that you may have having spikes/drops and those are what you’re thinking is other straps.

  97. I wish that were true. I didn’t even have my heart rate strap on one day and some other cyclists pulled up beside me. My Edge showed “HR Monitor detected” and I had their heart rate information until we were nearly 20 feet apart.

    I thought you could only connect with a paired strap as well. The only explanation is Garmin recycles their unique identifiers. Being in Denver, you can’t go 5 minutes without seeing another cyclist.

  98. The ride in question is right here:

    link to connect.garmin.com

    See how I have heart rate at 39:42 right at a light as someone pulls beside me. I continue to record heart rate until 42:10 when we are far enough apart. Since i didn’t have my strap even with me, I didn’t have heart rate for the rest of the ride.

    • Ray Maker

      You know, thinking back, there’s a bug I saw a number of firmware versions ago where the unit will go into a searching mode if it can’t find it’s normal HR strap friend – doing exactly what you describe. I’m pretty sure it was fixed though. Have you validated you’re on the latest firmware?

      Also, any chance for a soft-reset?

  99. Interesting, I was on firmware 3.0 at the time.

    I may soft reset, leaving for a self-supported trip in a week and don’t want to mess with perfection too much at the moment. :)

  100. Anna

    Great blog, excellent tips!! Thanks a bunch:) Anna from Hungary :)

    • werty

      Using alcohol works best in the U.S. due to the heavy metals in our environment which we sweat out…such as uranium, thorium, lead, etc. Surprising it’s such a secret.

  101. Jarmo

    Is anyone tested single used (ECG) electrodes for heart rate monitor? Normally the snap connector is “male”. For Garmin and Polar it must be “female”! Have you seen that kind of electrodes?

  102. Casey

    Those are all interesting theories but the truth is that it’s a shoddy product that is not durable. When my heart rate starts to spike as you describe I replace it with a new one and then it works again for about 30-60 workouts. I go through about 6 straps a year. There’s no need to pass on excuses for garmin — they ought to make a better strap. Each of the theories you describe would make it a product that is not fit for its intended use in normal operating environments. But it’s primarily a lousy product that wears out faster than it should.

    • It’s not specific to Garmin HR straps you realize. It happens to users of every HR strap brand, and even brand new HR straps. Connectivity issues tend to be highly unique to a given issue or situation.

      The steps above seem to help a lot of people, so I don’t think it’s about excuses, it’s really about just helping people.

    • Mark

      That is so true !!
      I go thought a few straps per year and rather go though the hassle and waste of time I purchase a new strap aldo

  103. Donny Semple

    I have a cardiac pacemaker and get no sensible readings from my Garmin Forerunner. I’ve tried electrode gel and get erratic readings ranging from from 0 to 200

    • Hmm, if you’ve tried gel, that is a bit odd. I just don’t have any experience or knowledge of how the pacemaker impacts the strap from a readings standpoint. Sorry!

  104. Rich

    Well, always being the adventurous type, I tried your licking trick and it works! My 60beat had completely stopped working and I had tried cleaning it with dish soap, but this evening I tried licking it and it works now! Weird. Thanks. Maybe I need to clean it better, probably just has a bunch of body oils on it. Tasted kind of funny too.

  105. Lindsey

    Great article – I am using a Polar transmitter with a Garmin wearlink+ strap which seems to give me very high (220bpm) readings to start with but then settles down.

    Just a dim memory from my Engineering past – water doesn’t really conduct electricity. It is the salts in the water that conduct – so saliva / sweat should work better than tap water, although the latter will probably get some salts in it fairly fast from the hrm strap / skin.

  106. Steve

    I’ve got a Garmin 310XT that recently started giving me consistently high readings. Like a constant 230 while it should have been down near 160. Tried everything – watch reset, battery change in the strap, wetting the contacts, changing position. Nothing fixed it.

    Finally on my run tonight, I unsnapped both sides of the strap from the transmitter (I had always been unhooking it from one side only). Reconnected it and the heart rate is back to normal. I assume the snap also acts as the contact and it had corroded enough from sweat that it wasn’t making good contact.

  107. Peter

    As ever a great article followed by a lot of insightful comments.

    The main conclusion to be drawn is that these things have been around for over 25 years but some users are still getting an unacceptable experience despite taking incredible precautions. Hopefully someone can solve this one day. Watches are progressing so fast but one component, heart rate monitoring, can be unreliable. Query whether the new Garmin 620 or PowerCal have taken this forward at all as they are bringing the focus back to the heart rate strap with extra functionality.

    The other issue touched on above but only briefly is athletes with cardiac history. Monitoring heart rate is pretty critical for them and erratic nuisance for an average user may be a false negative tachycardia or general arrhythmia for someone with cardiac issues. A false negative does not make it any less worrying.

    Without wishing to worry anyone at all, while I am sure that most of the errors are down to the kit, some athletes will have cardiac issues, perhaps intermittent, perhaps without symptoms and many will not know, thinking that exercise confers immunity. One cannot guarantee that the kit is always at fault for all users. If you think you have had an incident, go to your doctor even if you think it was not important or was quite subtle. Even if you have not had a known incident then seriously consider cardiac testing as a wise investment for an endurance athlete – it is your engine. I say this because I have had many of the experiences that others describe above. However, I have also had a competitive running friend die of cardiomyopathy and a cardiac incident that initially I thought was just a poor run but caused me to require every test going – all cleared (thankfully) after 6 stressful months. I think I can now spot the difference between tachycardia and artefactorial error in the HR graphs as well as knowing what a cardiac incident feels like. That is why I measure heart rate and am keen to get accurate numbers. Accurate numbers may matter more than some commentators above realise.

    • Andrew

      What type of tachyarrythmia have you experienced ? What were the symptoms and triggers ?

    • Esterhase

      Well said. A HRM is not an egg timer. I’m well past sixty, and it makes a big difference to me if i’m at 80% or 85%. One comes to depend on these things to give reliable information; having it go to ’00’ or ‘237’ in the middle of an interval is distracting, to say the least.

  108. Garmin 910XT. I was a little worried today after I uploaded the data from my run. Not having a good run and not feeling strong on the run, when combined with a totally out of kilter heart rate spike, just as you depicted, was a little unsettling. Fortunately, I had my wits about me, and typed a query to the net to see if anyone else had a similar experience with the Garmin 910XT. Sure enough, I found this post. To the point, good info. Today was one of our drier days, I was in a tech shirt, and had not put any water on the HR sensors. I am most grateful for your post. Thanks.

  109. Paulo

    Hi! I ‘had a lot of problems with the HR values (very unstable and high values!) of my 310 xt and nothing I tried to solve the problem seems to result!! I contacted the technical support from Garmin and they can´t help me, just entertained me!!! I´m a biomedical scientist and a remembered that when we had problems of bad connection in our analyzers we clean it with alcohol 70%, and I tried this method! I cleaned (Washed!!!!) the contact points of the strap with a lot of alcohol 70% and miraculously it seems to RESULT!!!! After that I used the HRM for 2 times and the values are more stable!!!
    Hope that post can help!!!

  110. Alejandro Lemmo

    Hi, I having issues with my hr monitor, but I can’t figure out what is wrong with it. It was working fine for about 20 rides, I followed the instructions given by Garmin, on how to set it up, and wear it. I also dis what you suggest in this post but it is not working. The hr monitor apparently starts fine, I wet it before wearing but after a few seconds the 310xt stops reading as if I removed it from my chest, and then all the reading it shows are as if I were at rest even thoug it ahould be at least at 150 or 160 bpm. I have no idea what’s wrong. I even replaced the battery with a fresh one and the issue persists. Any suggestions?

  111. A.Lettriste

    I have used 1 Polar and 2 generations of HR bands. All of them fail, sooner or later. All of them have had build quality issues. After reading the recommendations by Garimn, it was pretty obvious that the source of nosie in HR readings was static electricity. Dry air, tecnical garment, vs. moist, cotton, etc. all indicates that building static electricity between some part of the band and the body (and then releasing it suddenly), may create the spikes.

    In October I bought my 3rd generation Garmin HR band (010-10997-07). I cannot comment on aging since I lost it a week ago at the gym, but readings seemed to be quite correct and stable (I am using a 910xt). The most noticeable aspect of this band is what looks like a static shielding, on the OUTSIDE of the band, that somehow is connected to tthe inside. In the instructions, you can read that you have to apply moist on both sensor pads AND the connector with the static shield. It seems that you “ground” the outside of the band, with your body. I used it for a month without any problem. Does anybody has used this new band for a longer span? It is stable with time? In addition, It may suggest some fixes to old bands…

    Cheers!

  112. Ken Parrington

    I have had my Garmin Edge 510 & soft Strap HRM for a few months. The HRM ha never worked correctly. I ran out and purchased a Polar Strap and still had similar issues. I then changed the position of the HRM by having one sensor on my left side and on on front of chest. This was the first time I had taken reliable HR readings. This was using the polar strap. I am yet to test in the new position with the Garmin strap. The other thing I have wondered is whether this issue mostly plagues those of us with a lot of chest hair? Anyways…. Now happy I can get HR info. The suggestions from this site have been very helpful.

  113. muhumm

    “Also note that you cannot mix Polar HR straps/units with Garmin HR straps/units”

    you meant that you can’t mix polar HR transmitter with garmin transmitter, right? because the strap itself can be mixed around just fine. e.g. I’ve used garmin 910xt watch with polar RS200’s HR strap, locking the 910xt’s transmitter onto the polar strap (after removing the RS200’s HR transmitter).

    another correction:

    “if it’s over 200bpm, it’s likely not legit unless you’re a seven year old”

    I’m sure you didn’t mean that HR can’t ever go over 200bpm for people older than seven. maybe clarify what you exactly meant? like, 7 year olds can have 200bpm even during warmup?

    anyway, what I do:

    1. put HR strap on for exercise
    2. wet my hands with tap water
    3. push my hands under the HR strap on my chest, this will wet both the strap and my skin in one go
    4. I make sure I wet the strap right on the electrodes on both sides. full length of electrodes.

    that’s it, job done, works fine.

    if there’s still a problem, HR strap needs to be tightened.

    I use the hard strap, no soft strap for me, thank-you (I used the polar one when I didn’t have access to anything else)

    • I was simplifying on the first one. Yes, you can swap the strap portion, but not the transmitter pod. I write a full post up on swapping the straps: link to dcrainmaker.com

      As for the 200bpm, no, that’s what I meant. In general, unless you have some sort of specific condition, you’re heart rate won’t be above 200bpm. Thus, if you see a spike at 236bpm, it’s an issue with the strap.

      The reason I specified 7yo, is that most people start with the simple equation of 220-your age, thus, I’m joking when I say 7 year old. But sorta serious.

  114. Biastee

    “The Polar’s use electromagnetic signals to send the data from the coded strap to the watch, which can be interfered with by high tension power lines. The Garmin’s on the other hand use the 2.4Ghz frequency and don’t have the power line issues typically.”

    Both Polar’s 5kHz and Garmin’s 2.4 GHz signals are electromagnetic – just vastly different frequencies. Garmin’s ANT+ is a version of Bluetooth. By using 2.4 GHz, Garmin may be just swapping power line interference with Bluetooths & WiFi interference.

    “Replacing the batteries: Finally, last but not least – sometimes it’s just the batteries getting old.”

    I have mistakenly replaced batteries when the problem lies elsewhere. To avoid wasting usable batteries, I now measure the battery voltage before deciding whether it needs to be replaced. I have found that the 3.0V nominal battery begin to exhibit erratic readings when the voltage drops to ~ 2.0V.

    One problem that I have encountered with the Polar soft strap is a change in electrical continuity between the electrode and the snap-on button. When it is good, the resistance measures between 3 – 12 kOhm. When the connection goes bad, it measures >100 kOhm.

    I hope the above info can aid the faultfinding process.

  115. rojo

    I´ve just bought an HRM and it only takes readings when i inhale.

    I´m also kinda fat, could that interfere?

    Cheers.

    • Hmm, very odd – never heard of that. And never heard of weight being an issue with any HR strap. Have you tried HR gel to improve the connection (failing having gel handy, just add a bunch of spit first).

    • rojo

      Thanks for the prompt reply!

      I´ve tried new batteries, spit, and HR gel. Tried more and less tension on the strap, wearing on my back, and nothing worked out.

      Maybe the thing´s broken.

    • Biastee

      @Rainmaker. Maybe fat is a poorer electrical conductor than muscle.

      @rojo. The transmitter electronics can go bad. If you have a soft strap, the connection between the electrode and the button can also fail. In the latter case, you will only need to replace the strap.

    • rojo

      I just went to the store, and it worked just fine on the skinny little fellow that sold it to me.

      So fat can interfere with the functioning of the thing.

      Good news is that i finally made it work, I pulled the strap way up my back so it presses against the pec/b*tch-t*t.

      Cheers!

  116. A.Lettriste

    I have been using the hew HR strap from Garmin (010-10997-07), without any problem since october (well, I lost it and replced, but that’s another stuff!).

    Yesterday, when going to a HR guided bike workout I found I forgot my strap. A colleague lend me his older (premium) Garmin band. And spikes were back again!!! I am currently using HRV measurement (R-R) in my 910XT, so I ran the .FIT data into Firstbeat Athlete and… voilá… Firstbeat seems able to recognize spikes and to remove them very well. In addition, the smoothing is much more precise. I had done the same workout 3 weeks ago, and the smoothed profiles are quite in agreement. Another interesting thing to note is that running firstbeat, spikes do not show an “exponentially smooth” decrease, they are just spikes, so easier to spot. If needed, I can upload the pics qhich are quite impressive. On a side note I am using Firstbeat Athlete edition (80 u$s/lifetime license), and… this version does not export the results other than in Firstbeat propietary format, so I am correcting BY HAND the .tcx file…. :-/

    Cheers!

  117. Andrew

    Guys, cheapest solution I have found to work and eliminated any dropouts was what i did here. link to forum.slowtwitch.com

    • A.Lettriste

      @Andrew, Interesting. You are using the “new” (shielded) HR strap and it failed also. How long did you use it before noticing spikes?

    • Andrew

      Yes, it is the HRM3 version that has the shield all the way across the backside. I had it for about 6-8 months before problems started popping up. and it was more of having HR going to 1/2 of the actual reading than it was seeing HR spikes. I think Ray has the market cornered on the solution for that problem pretty well already.

    • A.Lettriste

      Blast! Thanks for the solution!!!!

  118. Amy

    Hi – in the last month my HRM has started giving me the 180+ average/over 200 readings (the problems you’ve described). I’ve tried all your key suggestions: more water on the band, electro gel, and new battery. Still not working properly. any other ideas what else to investigate?? Love your blog, thanks for all the good advice.

  119. Andy Cavanagh

    Hello, excellent blog, you’ve made put my mind to rest with a lot of the above. I’ve been using cycling to get fitter and lose some of the middle age spread I’ve accumulated between 40 & 50 Years old. I was/am doing great lost 10kg over the last 5-6 months. Then the scary happened, took a phone call while out the other day, work never leaves me alone, glanced down at my displayed HR on my auto stopped Garmin 510 it had peaked at 248 BPM, I had absolutely no other symptoms or indications of any cardio issues, still worried me to death though. caused me to ‘find’ your blog and wanna say a huge thanks for allaying any fears. Went out again today and hey ho, having repositioned the chest strap, apart from the odd ‘glitch’ all seems well. Yahoooooo!

  120. Eirik Degerud

    Thank you for posting this and for saving me 90$.

    Guess I am one of those with freaky anatomy as rotating the HR soft band 90 degrees solved everything.

  121. Hi everybody,
    I am noting (my last few runs) some problems with my hr band. Actually it gives very wrong results… not just at the beginning (as was getting used at that) but also during the run… so that suddenly it looses contact with my watch or it says I have 75bpm …. which is unreal if I am running up a hill.

    Are these normal signs of the battery needing to be changed? I was thinking of this… also if it is not that long I am using it… but I got it from a friend of mine, who was not using it, but maybe had it in the drawer for a long time.

    hope someone can give me an hint

  122. NewGarmin

    Hello everyone,

    I bought my Garmin Forerunner 220 about a month ago which came with Garmin’s Premium HR monitor. It has worked just fine until recently. Unlike most of you, I am getting zero reading. My watch is not connecting to the HR monitor at all. I’ve reset the watch, cleaned the monitor, gotten it wet, etc. could the batteries be dead already?? It’s only been about 3-4 weeks and I usually run a few miles 4-5 times a week. Please help.

    • It could be. Every once in a while I hear of a strap might get in a strange spot where the battery doesn’t go into standby and basically just burns until the candle is dead (battery).

      It’s a quick and easy $2 fix. But, if it happens again, ring up Garmin support and have them swap out the strap, as it’s probably a short in the strap somewhere.

  123. Robertb

    My experience is that the HRM works fine for months, then gradually starts to fail. I’m on my second now, which is starting to play up. Having read the comments above, I wonder if the problem is not between the contact patches and skin, but with the studs to which the HRM fastens; these are regularly snapped in and out, so maybe this causes a loose connection on the studs. Or possibly, the stress of the flex of being snapped in and off again causes the unit itself to develop an internal fault and fail. I’m going to try cleaning the studs and holes with electrical switch cleaner and see if that works.

    • Biastee

      I have experienced contact issues due to rusty studs – I didn’t follow the instruction to wash the soft strap after each use (I was accustomed to the hard ‘classic’ strap which didn’t need washing). But the studs have large contact areas and so they won’t fail until they are almost completely covered in rust. Another soft strap failed because of a bad connection between the stud and the fabric electrode. You can diagnose connection issues with an ohmmeter – see reply #128.

  124. gv

    Hi – Im wondering if you might have an answer to this. I recently bought the suunto ambit2 s. The hr works well till about 10 – 15 min into the workout then it starts to stay static at lets say 115bpm when im sweating bullets doing heavy interval training at the half hour mark..by then its still hovering around 115. Whats wrong here? Ive place the strap correctly and in the same senerio (other time)near the end of my interval workout ive peaked at 160. Any thought s? Thanks

    • I suspect you may have sweat pooling under the strap, which sometimes can cause issues. One option is change the location of the strap (move it higher or lower on your chest), sometimes that helps. Another is to rotate it to the sides of your chest, sometimes that also helps.

      And finally, you can do what I do when that happens – just wipe the sweat away from under the strap. Usually does the trick.

  125. actually, after I washed the band with no results, and finally lost the sensor in a trip (did not do it in purpose…)

    I am here trying to choose if to buy a third part sensor by decathlon, which I read should work fine , or the official garmin for twice the price.

    what do you suggest? I thought a lot about it and I am more into the bargain from decathlon. link to decathlon.fr

    nevertheless I ll let you know when I use it if I buy it.

  126. I have the Garmin HRM strap that came with my 620. I’ve had the strap since November and it still has the same battery. I ramped up to 35-40 miles per week in the last few months (to give you an idea of my usage) and have never had issues with the strap until this week. Tuesday I did an 80 minute run (9.5 miles) I saw my HR go from 170 down to 140 between mile 6.5 and 7.5. The HR went back up between 7.5 and 8.5 and came back down to 140ish for the remainder of the run. This morning I did a 6 mile trail run and the last 1.5 miles saw me go from 170bpm down to 127-140bpm. This morning the rain was pouring and I was constantly pulling my HRM back up. Could this be a placement issue or could my heart rate really be dropping even though my effort isn’t? Could the battery be low? BTW, Wednesday I had no issues. The HR remained constant on my 5 mile run.

    • No, it sounds like just some of the normal issues that you can use gel for, or some of the other solutions to try and alleviate.

      That said, the FR620 comes with the HRM-RUN strap, so most of those don’t tend to happen with that strap, it’s usually pretty good. You could swap out the battery, in case for some reason it’s on its last legs. Typically they last a year or so, but sometimes they can get in an odd state and burn through battery while you think it’s off.

  127. Hey Ray! Hope you are well.

    My heart rate data on tonight’s data was consistently very high (220-250). On recent rides it has also been spiking. However, nothing like tonight–training peaks even emailed me to suggest to increase my threshold HR to 180 BPM on a night I wasn’t really pushing!

    Do you think this could mean a new battery is needed (trainer road tells me it is almost 500 hrs since a new battery)?

    • If it’s random spikes, it might be a new battery. But, if it’s constant highs (like the 220-250), then it’s something else – perhaps jersey flap or the like from the wind.

  128. CiCi

    I am going to try all the suggestions above and hope it will save me a trip to the cardiologist. I am a very senior runner worried about the spikes in my HRM. I show spikes over 200 even when I am at conversational pace and breathing easily with no perceived exertion.
    I have not seen this mentioned, but would a well endowed woman have issue with HRM picking up bouncing breasts? Please this is serious no jokes.
    I have the 310 xt.

    • Hi CiCi-

      I’d definitely try all the suggestions first. I haven’t heard of any women finding correlations between those two. In theory, yes, repetitive movement is often picked up by heart rate straps as heart rate. However, typically that’s running cadence reverberating through the body (many will find that when a HR strap goes wayward it actually matches your running cadence – or double your cadence). But, I don’t think there would be enough of a sharp signal from breasts bouncing to cause that pickup.

  129. Fish

    Just got a new FR610 and HRM. The HRM seems to only read – – – (0) or 103+, any ideas?

    • I’d try swapping out the battery on the HRM first (I know, sounds silly, but sometimes on units that have sat on a shelf a long time the battery is basically 99% dead). If that doesn’t work, ring Garmin, something is definitely wrong on the HRM strap.

  130. ComPH

    Thank you for this web site. I would like to add a little to the point of the strap positioning. I have been fighting reliable HRM output for couple of months. Tried everything, new straps, couple of different sensors, gels, metal inserts over the electrodes, nothing worked reliably for long. In the past few days I discovered (and tested) position that works for me reliably, long term, with ALL the straps. I positioned the sensor electronics right under my left nipple. This is working dependably in four different systems. It makes sense, the heart is slightly towards the left of the center of the chest in most cases. I thought I would share this information to save people the same agony and frustration I went through.

  131. Willem Smeenk

    I solved the problem with the HRM output the same way as ComPH. I found that before I haver read this post ( sorry for my English, I am Dutch )
    Last sunday i desperate change the possition of the sensor on the strap to the left. The SIDE of the sensor is now on the middle of the chest. This doet the trick! No problems anymore. Ive looked for more than a year for this solution and tried everything.

  132. Paulo

    I solve my PROBLEM!!! I I by a HR strap from Dechatlon
    for half the price!!!!!! and perform great!!!!!! I recomend!

  133. Dave

    The wearlink belt works great with Bryton ANT + HRM too. My original HRM was reading upto 250bpm and when resting nothing lower than 150bpm. I swapped out the bryton strap for a Wear link strap and straight away, resting heart reat 56bpm and holding. Thanks for the great advice.

  134. Mickey

    Here’s I riddle I’d like to figure out: Got a Forerunner 310XT w/HRM paired it up no problem, put it on (with all the appropriate wetting, etc.) No heart rate – rode 25mi lots of hills – No heart rate. Put it on my wife works great – put it on a friend works great – put it back on me, No heart rate. I went so far as to shave my chest. I’m fairly certain I have a pulse . . .
    Has anyone ever run into something like that?

  135. Craig Baird

    Hi Ray – Thanks for the info on the HR monitor & troubleshooting tips. I’ve had a few questions about my Suunto monitor recently, one of which you might be able to shed some insight. Looking at your HR graph I see where you have two dips in it after about 1 hour. I’ve gotten back into running and have noticed that after about an hour my HR has episodes of dropping, and in some cases will race back up when I stop running. I’m in my mid 50’s with a current max. HR about 188, and I’m trying to keep my rate around 150 on my long runs. When it does drop it goes down around 120, and on a few occasions when I stop it will race up to 160 & then drift back down. I’ve never had any adverse symptoms other than what one would expect from running for an hour. I’ve heard of a few people mention this type of episode but they haven’t been concerned. Have you ever experienced a HR pattern like this or do you think it could be the monitor? Thanks –

  136. Sebastien Garcia

    Hi

    I’m experiencing something slightly different with my new Ambit2 and suunto ant strap.
    After 40-45 minutes, no more communication anymore between the 2. flat HR graph ( link to movescount.com ).

    Stopping the move and starting a new one and HR is displayed again (but movescount cannot merge moves)

    and of course there is plenty of sweat involved…

  137. Chad

    Does rain affect it. I have been using my FR620 strap about 4-6 times a week for about 6 months and today in the rain the reading were all over the place. I use the electrode gel so that is not an issue. Could the battery be dead already?

    • No, it shouldn’t have any impact unless it’s really pooling (the water). Sometimes batteries do go a bit early if the unit got into a weird state where it somehow was left on for say 24-48 hours (the strap) and didn’t kick into standby. No worries, batteries are cheap.

      I see that once every few months from people from a variety of vendors. Nothing widespread, but does occasionally happen.

  138. Paul Bridges

    In endeavouring to resolve my Garmin Edge 705/HR Strap I came across your posts which were really interesting. However, my HR does not register on my unit. I have changed the battery but without success. I have emailed Garmin support but no response. At considerable expense I have purchased a new Garmin Chest Strap but still no response! Any ideas so that an old boy can get on his bike and monitor his heart rate?

  139. Matt

    Hi Rainmaker,
    I got some problems with my HR monitor: when I start running the heart rate drops down as you can see in my last activities link to connect.garmin.com
    Of course the registered bpms do not represent the real heart rate. Garmin support only suggested me make a reset of my 910xt, but this did not solve the problem. I also replaced the battery which seemed to be discharged. Also this did not give any good result.
    What else do you suggest? Shouls I send my device to the support for repair?
    Thank you for any answer.
    Matt

  140. Gyuri

    Yes, saliva works much better than water. And you get back the salt you lost during your former workout. :) I got addicted to licking my strap after reading this post.

  141. R. Mac Key

    Info only -good to know tip:
    I have used many cheap analoge 30 usd heart rate monitors. They have been working fine most of the times.

    They have also synced with most of the heart rate monitors on gym equipment at various gyms.

    Interesting is that my headphone cord connected to my litle portable radio interfered the readings a lot sometimes. Especially when swinging/banging on the sensor strap.

    Surly an analoge beep signal is a lot more sensitive than a digital coded signal I higher end equipment, but I may be good to add to the problem check lists.

    (cr2032 strap and watch batteries are now available at IKEA for like a 0.20 USD nowdays)

    Run Forrest run.

  142. Runpol

    I’m unclear what type of signal is transmitted between the skin and the belt sensor to indicate heart rate.

    If it is electrical, it would require a reliable EKG setup, essentially four electrodes glued to the skin with adhesive and without a moisture conductant, wouldn’t it? This doesn’t seem to be the case with the Garmin belt. This is different than blasting the body with current as with heart paddles or electric chairs, both facilitated by moisture but involving a lot of electricity,

    If it’s sonic as in ultrasound, it would require gel or moisture to eliminate air between the sensor and the skin because air doesn’t transmit the sound signal.

    If it’s pulsatile motion activating electrical sensors in the belt, it seems there would be a lot of interference with breathing and other movement.

    What kind of signal is the belt receiving through the skin?

  143. Ray Fryan

    Hi Rainmaker,

    I have a ~3 yr old 610 with the new soft-strap design. I’ve been aware of the getting the sensor pads wet with sweat or spit, and up until late this summer, that worked fine – all 4 seasons. I recently replaced the soft-strap (~Sept) when the late summer heart readings started to get less consistent. Initially, the new strap seemed to work better.

    I’ve scanned the many posts and your responses. I think I have tried nearly everything:
    Using electrode gel – same as your picture!
    Have tried cotton shirts, even wetting the area of the shirt in contact with the heart monitor. Doesn’t keep the crazy spikes from happening
    Am spraying my tech shirts inside and out with static guard. Seems to help for the first ~10-20 min. After that, the heart rate reading spikes to between 180 and 240.

    We are in a relatively dry winter in NE Ohio, so my inside/treadmill runs are pretty dry, and I’m sure the static level is high. This morning, tried to move the strap so that the pads were in the middle of my back. Didn’t help. I then moved the unit to the left side of my chest. This DID help, with only 1 spike in about 20 minutes.

    On certain runs on the treadmill, or even outside, I have gotten so frustrated that I took the thing off and put it in my pocket or in the cupholder of the treadmill. Most of the time there is still a reading. Not sure how that happens!?!

    Thanks in advance for any advice you can provide.

    Regards,

    Ray

    • biastee

      Ray Fryan wrote:
      > Using electrode gel – same as your picture!

      When gel/spit doesn’t solve the problem, the most likely problem is broken electrical continuity between the snap-on button (on the strap side) and the electrode. This connection can be checked using an ohmmeter. A bad strap will measure tens of kiloOhm upward between the button and the electrode. A discontinuity at either left or right connection will render the strap useless. If the discontinuity is confirmed, the only solution is to get a replacement strap – either an original or a knockoff from China can work just as well.

  144. Mark

    I have a Polar RS800CS and have been getting frustrated with irregular high readings, mainly on cooler mornings. I ride the same route often so know its not due to power lines interference etc. I noticed that it seems to be when cool and windy. My heart rate can be all over the place but if I stop riding the reading normalises. Figured it was the flapping/static of my cycling jersey, in desperation I rotated my HRM strap around so it was taking readings from my back. Fixed the problem straight away due to less wind/flapping/static on the back of my jersey

  145. Greg Hilton

    does anyone know if I can wear two different bands and have them broadcast to two devices without them interfering?? I think my origional Garmin classic band is broken so a friend has lent me another one. I’d like to ride with the new one linked to my Garmin 810 and the old one linked to my Fenix.

    Then I can hopefully compare them side by side!!

  146. Graham

    Hi,

    I get a similar problem buts its started happening after about 10km on my last few runs. HR steady at about 150 upto that and then suddently starts rising up to 220 over a coupld of km’s for the same effort and RPE – don’t think any of the issues about could be causing it. It doesn’t happen on the bike though? any thoughts?
    Cheers

    Graham

    • Any chance there’s a lot of sweat? I’ve seen some rare cases on super hot/humid days where I’m just dripping sweat and it’s almost ‘pooling’ under the strap when I’m further into longer runs. In that case, I’ve found that by just wiping the sweat away it seems to solve it.

  147. well getting a second one either shocked the first one into working properly or I was ill, or there were some strange happenings going on midweek!! It did two over 210 readings last week and was all fine by Sunday!!

  148. I think it’s down to two particular T shirts I wear. Sat/Sun was ok biking, lunchtime today with the same T shirt as last week and it went to 227 max!!

  149. Alex Ellis

    My Garmin standard semi-rigid HRM works fine on my bike with my Edge computer, but as soon as I go for a run/jog I find that after a few paces my Suunto Ambit 2S is showing “—” instead of a HR figure – sometimes over tightening the strap works – but not always. It may come back and then half way down a road I’ll look again and the number has gone.

    It’s definitely very moist at this point too. I’m considering for running alone either the Garmin premium or Suunto premium strap – do you think either would help resolve the problem? I usually run in a long sleeve wool ice breaker.

    • John

      Did you resolve this issue?
      I have exactly the same problem. Strap is about 6 months old and I put in a new battery when the problem started, but that did not fix it. It results in an exercise move with large stretches of flat-line HR (e.g. at 150 bpm) or drop out/ no reading at all for long periods.

    • I recently bought second hand Suunto Ambit 2 with HR strap in the package. It was showing correct HR data for the first several workouts. After that it started with the same issues, showing high HR when I am in calm state and do not exercise, stopping to show HR current BPM. The belt pairs just fine, the readings are the problem.
      I changed the batter with a new one – no success.
      I did restart of the strap as shown here link to youtube.com – no success.
      A lot of peoplpe have the same problem on Suunto forums, and some say the problem is in the electrodes in the belt, that tend to loose elasticity and start to show incorrect data.

      I will probably go for another brand of HR strap, since the Suunto replacement belt has similar price as a brand new HR sensor + belt from similar brand and probably Suunto belt will break again in some time of extensive use.

  150. Andrew

    Any idea what might cause a — for lack of a better term — hairy HR graph? First image is from a treadmill run Jan. 12, and looks fine. Second is from Feb. 13, and is what it’s more typically starting to look like. Same strap, same gym, I’ve tried gel and washing and wearing cotton instead of synthetics. I was thinking static electricity, but I’ve taken steps to minimize that (short of using an anti-static spray) without much help. I bought a Garmin original/hard strap to try to minimize this (soft strap I had was perhaps worse, spiking into 200s instead of this more “localized” spiking). I’d hate to think it’s already toast after 4-5 mos., when a lot of people say this model can stand up for years.
    Graph one (good)
    Graph two (bad)

  151. Archaeo80

    Hey Ray,
    I’ve been running with the Garmin HRMRUN strap for a little over a week, and I’ve gotten consistent and accurate results. My issue is the strap keeps drifting down due to my torso shape. I’ll start a run with it at the base of my sternum, but after a few miles it always settles about 3 fingers lower no matter how tight I adjust the strap. Do you have any suggestions? Or should I just let it be since my readings seem accurate?
    Thanks!

  152. Jess

    I have read a lot of questions but none have addresses my issue.
    Our vivofit2 with heart rate band are only a few weeks old. I am having issues with it reading heart rate.
    I do use saliver each time but it is not helping.
    Is it likely an underwire bra would effect readings, I am well endowed and need to wear this type of bra.
    I Also have a LAP Band fitted to my stomach and the port is right were the middle of the band sits. I can not raise it as the breasts stop it from moving up.
    The issue with the band is it will not hold a reading connection, it keeps loosing the readings.
    The last walks had six breaks of no readings, I think it only linked back each time because I went to heart and then it started reading again.

  153. Katherine

    I’ve been using the forerunner 910 xt for a few years now. She’s a beaut. However recently, the HR went all berserk. I am currently laying down. My HR according to my fingertips and wall clock is under 70 and my watch is showing 200+. I’ve relicked it. Changed the battery. Repositioned. Nothing. According to my watch I’m still about to have a heart attack. I want so badly to return to the days of training in zones. Please help. ?

  154. PelleG

    Hi Ray and everyone else.
    First off thanks for a great site and great useful reviews and discussions.
    I seem to be having a similar problem to many of the other posters of slightly low HR readings. I am using the Garmin HR run strap with edge 810 and Fenix 3. The readings seem fine at low to moderate activity but at HIT my HR will stay in the 160 to 170 no matter how hard I push. Max HR is 192 (or was last winter). The issue arose from one day to the next and I nearly fainted pushing myself in the intervals without getting near my target HR. It has been like that for the past few month now. I have tried moving the HR strap around, with no luck. However not on the back, must try that as well. The thing is that the HR strap worked fine up until the time I got the Fenix 3. I don’t really see any connection however. Any ideas, or should I just get a new strap?
    Cheers
    PelleG

  155. Andrea Assanelli

    In my experience, when things go wrong they go really wrong. You can spot irreguar readings very easily in a 910xt. If you want to be sure, the best way for me is to record de R-R data (HRV). Some programs can extract this info from a .FIT file and you can check it in a spreadsheet. Most gramin devices I have used, do some kind of average of the missing data, giving some bad results. But what you see is a mix of the missing data AND the Garmin averaging. Looking directy at the raw data (R-R only!), gives you a hint of what’s going on. Firstbeat Athlete does a wonderful job in sorting out bad data.

  156. john

    A couple times of late my garmin hr premium will just show a declining heart rate from about 2/3 of the way through a run – so instead of showing, say, 165 and rising, it will just go steadily down so it is at 100 or so when I finish the run- and my actual hr is for sure maybe 170. Anyone seen this?

  157. MrSwadge

    I recorded some strange readings on Monday night. I think it’s down to me losing weight around my chest. The strap simply needs tightening up. I haven’t done the licking thing though, so I might well add licking to my armory too.

  158. Hello. I ran 50 km recently when at 30 km I saw my hartbeat at 70/min. Later it went down and down to 40. Of course in real it was around 150. Anyway for next run I changed battery and I keep having the difficulties. Displayed frequence is from 50 to 70 but real is cca 150 – 170. Sometimes measurement disappears at all :(

    I have belt from garmin 310xt.

    Anyone knows how to fix it? I always make my chest wet and belt too but still not helping :( Thanks a lot in advance for your help.

    • biastee

      You didn’t say whether it is a hard or soft strap. If it is the latter, you can move the detachable transmitter to a new strap and see if the problem resolves (ersatz straps are cheaper than the original and are as good). The most common problem with the soft strap is a poor connection between a snap-on button and an electrode. You can test the connection with an ohmmeter – a good connection is less than a couple of kilo-ohms. The transmitter can go bad too but this is rare. To test the transmitter, press it firmly on the fleshy part of your abdomen slightly below where the belt is usually worn. It should pick up your heart rate after a minute or so. An alternative way to test the transmitter is to attached one end of a wire to a snap-on button while using the other end to tap repeatedly on the other button. If the transmitter is working, it should transmit a reading proportional to the tapping rate.

  159. Jakob

    Hi there,
    could someone tell me how to easily fix faulty readings in Polar flow? I know how to edit the TCX file but I have no clue about how to re-upload it to Polar.
    Thanks

  160. Queenie

    Anyone have a tingling sensation where the electrode side touches your skin? Almost feels like a tiny zap every once in a while…

  161. Joshua Tracy

    Regarding the heart rate monitor for the FR 620 and quite possibly other similarly manufactured sensors (two halves glued together) I have discovered, after Garmin tech support and all other sources told me to either buy a new watch or sensor, I thought I might have a closer look at it. I wish I had taken some pictures for this. When it was new I noticed that the snaps were attached to the back half of the case, but when I wanted to take the sensor off the strap, the natural pulling force seemed to tug on the FRONT half of the case. upon closer investigation, I could see that this caused the two halves to begin pulling apart. The two case halves need to remain perfectly sealed to keep water off the little circuit board and electrical pathways for the sensor pads on the strap. I had all the typical issues with the sensor, then all of a sudden, it read high (220-245) all the time. So, I decided to pry the case halves apart and see what was going on. Sure enough, water and sweat had been getting in, and had caused corrosion on the tiny terminals for the pathway from the strap to the circuit board. I cleaned it, put some dielectric grease on the metal parts inside the case on the contact points where electricity from the battery should go, and sealed it back up. Good to go. Normal heart rate with no more spiking. I also just get the whole strap wet to begin with and it doesn’t slip and has good conductivity.

  162. pault

    My Garmin HR monitor was giving wild results even after I disconnected it from my strap and stopped to hold it in mid-air! any thoughts? I’ve since tested the battery with a multimeter and I’m now sitting, typing, with it on and it’s fine. Pic attached of a recent ride where I finally ‘lost it’ and turned home out of annoyance (after resetting/re-pairing the HR monitor to my Edge 800 at around the 12 minute mark). nb I know that I rarely exceed 170bm (I’m over 50 and normally ride between 135-160) yet it peaked at 240 even with it removed from the strap ensuring it was not making contact with anything (I’d taken it off at around the 13 min mark I think).
    Anyone else seen similar?

    • Greg Hilton

      I get big over 200 spikes, I got my heart checked out, I have an irregular heartbeat which causes this the specialist said he sees it a lot in older cyclists (I’m 49)

    • pault

      I understand what you’re saying, but I know what my heart does normally, and have had a cardio test, but when your hr monitor isn’t on your body then clearly it’s not your heart that’s being recorded ! Quantum entanglement perhaps?! as there was no other cyclist, or person, within half a mile of me when it went haywire

    • Greg Hilton

      ah sorry Paul, didn’t spot the bit about it not being on your body!! If it’s within warranty worth speaking to garmin??

    • pault

      Thanks Greg. It’s 4 years old now but tbh it’s fine most of the time (I keep a spreadsheet of my ‘efforts’ which makes comparison of similar things much easier than GC or Strava ). The HR monitor did play up for a while back in late 2014 but the purchase of the Polar soft strap seemed to cure it. I also had seen the occasional spike due to the flapping shirt syndrome and have shifted the sensor around to the back on occasions.
      This recent ‘working whilst off the body’ bit of craziness reminds me of an issue I had about 2-3 years back that caused me to wonder if the HR reading was actually a modulated speed/cadence signal being read as an HR signal (see image) – I wonder if this rings any bells? Though I wonder if the pauses in pedalling were points where I was adjusting things. I may check/change the battery in speed/cadence sensor too even though it’s doing it’s job perfectly.

    • pault

      Update. Whilst a new battery in the HR monotor didn’t seem to fix it (leading to more frustration during a recent ride and the HR subsequently being turned off), I tried a new battery in the cadence/speed sensor and, even though this battery didn’t seem to be low, the problem seems to have almost resolved itself – I say ‘almost’ as I still get that first blip of high readings due to the sensors not being damp enough when going downhill (shirt-flap?). Still it went for over 4 hours without a real issue – I wonder if the cadence/speed meter starts sending extra spikes when the battery is low or maybe it just needed resetting (was it actually interfering?)

  163. Anonymous

    I’ve had problems with it losing HR after an hour, drop outs, etc. While cleaning helps, I tried putting some connector grease on the snaps. Over 2.5 hour ride today and no issues.

    Connector grease is cheap, every auto store carries a small pack (more than enough for a year) for less than a dollar.

  164. Jeff

    I don’t know where to turn. Got new hard strap Garmin HRM to replace same used for many years till it became unreliable and erratic. New one worked perfectly from 12/26/15 – 5/12/16 and just stopped the next day. FR 50 wouldn’t pair, no signal at all. Got an FR70 and wouldn’t work with that either. Heart icon beats on watch indicating it’s looking for HRM but never get reading. Garmin sent replacement soft strap. That doesn’t work with either watch. No heart rate, no nothing. Put brand new batteries in both, checked voltage (3+) so batteries are good. I’m at wit’s end. Tried water, saliva, sensors are wet. I’m at wit’s end. Could my body’s electrical circuits be at fault? Totally baffled. Are there any tricks you know that I could try? I’m becoming resigned to not having heart rate data but don’t want to give up yet.

  165. Marcus

    My solution for heartrate reading dropouts, which didn’t even stop after replacing the HR strap with a new one and drove me nuts, was to open the transmitter pod and applying WD-40 spray (link to en.wikipedia.org) to the contacts inside (between the battery and the pod) and the connectors between the pod and the strap.

    WD-40 also helped me making my Suunto Ambit work again after one of its buttons didn’t move anymore last winter after about a particular wet and cold run. Great universal product.

    Thanks for this thread and the website, Ray and everybody who participates in the comments. Hope I can add something valuable for another reader, too, with this and helps saving some bucks erringly spent on new HR straps.

  166. Jerry Bolton

    Thanks again DCR,
    I’ve just done a very short ride (19 mile) and was alarmed to see my heart rate shoot up to 210 (from a constant 150-160) for nearly a mile.
    Para 3 (root) above hit it, as the course was flattish, but into the wind, and the HR dropped vertically when I turned a corner to go downhill.
    Or, its more serious but, hey, never mind.
    Also came to my aid about using the Garmin 820; their manual is next to useless
    Always recommend your site
    Cheers

    Jerry from Jersey (no, not that Jersey, the one 60 miles north of St Malo, some 4 hours by car west from you).

  167. Silvio

    Thanks for that, very useful !
    Talking about cheap gel … the exact same gel/contenance costs over 38 euros here. link to amazon.de
    Crazy, no ? And that’s from Amazon …

  168. Flip Viljoen

    I found your post very useful and informative. I have been struggling with the problem of false heart rate readings on both my Polar devices. the 752X using sonic transmission and my new V650 that uses Bluetooth. I have done a battery change and intend using ECG gel in the future. Many thanks

  169. Julie

    For females, but sure to not wear the transponder and electrodes under your sport bra. The friction from the sport bra messes up the readings. I have nothing but trouble with HR straps and think they all stink. When changing the battery on the Garmin straps be super careful not to strip them. I’ve stripped both the coin changing and small screw doors on different straps. Neither was my ‘fault’ as multiple people tried to get the doors off without success. This is a good article for the common problems, but there is no guarantee fix. My HR is usually wrong until I’ve worked up an very wet sweat and even then, there’s no guanatee it will correct itself. I’ve taken to leaving the strap off unless I’m intentionally doing a HR workout because wrong data is more frustrating than no data.

  170. Andie

    The thread might have been started a while back but the issue is still live. I too was getting similar looking graphs and wondering if it was me or the HRM that was at fault (and then which of two straps or the unit or the watch that was the root of the problem). The awesome spit ball wasn’t doing it for me.

    I went to the chemist and asked for “some of that water based gel they use for ultrasounds”… they didn’t have any of that, but after some umming and ahhing lead me to a rack that contained, amongst other items, KY Gel. I’m not sure they were swayed by my explanations of heart rate monitors and electrodes etc, but anyway I can vouch that KY Gel does indeed do the job (of fixing the erratic HRM readings) 100%.

    Thanks DCR for the solution, and the reassurance that it’s not my heart that was at fault.
    cheers!

  171. Gill brown

    Watch was on spin bike bar, close to computer. Moved the watch away from computer a voila.

  172. Lee

    I’ve never had heartrate strap issues ever until the last month and a half. Ive replaced batteries, straps, even the actual pod that snaps to the strap. I started using electrode gel and I thought the problem was solved but is still there. When I first put the strap on, the monitor reads 72 and doesn’t move no matter what I do for the first 5 minutes. Riding the trainer my heart rate just stops reading at the 35-40min mark and will not read anymore. I’ve never had this problem before and have gone on 5+hour rides with my heartrate being read the whole time. Am I too sweaty on the trainer? It looked like the gel worked better for the heartrate getting picked up in the first place but I can’t get past the 40min mark with working heartrate.

    • Lee

      Brand new strap, brand new transmitter and everything is good so far. I think I had issues with both. New transmitter on old strap didn’t work. Old transmitter on new strap didn’t work. Both scenarios gave me the same drop of heartrate at 25-40minutes. Went for an hour ride with all new setup and it works. We will just wait and see how long.

  173. Bob Tubb

    920XT and HR Premium. My problem is that this works fine on either run or bike but if I do Triathlon and wear the HR in the swim I don’t get HR readings on either the bike or run legs. I read somewhere that it could be static from the tri suit affecting the HR but if that’s true all tri athletes should have this problem. I’ve already replaced the HR battery with no effect. Any ideas?

  174. Michael

    My Garmin HR monitor (about 4 years old) recently started spiking into the mid 200s, usually on descents or flat sections of a ride.
    I finally opened it up and found condensation/moisture inside the battery compartment. I dried it all out and lubed the O-ring, but the next ride same thing. This time there is obvious rust and corrosion in the battery compartment, so guess there is moisture (sweat) working its way past the seal.
    Can I use my FR 935 as the HR monitor with an Edge 520?

    • Paul T

      Sounds like the old ‘jersey flapping static syndrome’ to me – if I hold the monitor to my chest, and thus pressing the shirt flat too, the problem tends to do away. Give it a try on your next descent

  175. Robert Prater

    I use a Garmin soft strap with a Garmin 1000. I have been having problems with the unit dropping my HR completely or sometimes showing half the normal HR.
    I returned from a ride and experimented with holding the sending unit with my wet thumbs against the contacts and it worked normally. I also was able to push the contacts into my chest and get a reading. I was still sweating, but went ahead with licking my fingers and smearing my strap with spittle just to ensure it was wet. Best I could do with the strap was to get a few readings right after I moved it or pressed it to my chest. Even these readings were about half of what my heart was actually ticking.
    I have read in other posts where people have cut the strap behind the sending unit so I took about 1/8 inch out of the strap behind the sender. Cutting the strap like this would eliminate any short circuits across the strap contacts due to salt impregnation. This makes it easier to put on, but did not solve my problem.
    Thinking that if it not shorted then it may have high resistance I cleaned the contact areas with rubbing alcohol and presto! I have been washing the strap as recommended by Garmin. However, I think a layer of body oil builds up on the strap insulating it from my skin and maybe my hypo-allergenic high efficient laundry detergent didn’t cut it.

    • Lee

      My soft strap would cut out after about 45mins. Or read half, would stay stuck at 76 all the time. I washed it, cut it, started using gel, nothing worked, when it’s broken, it’s broken. What did work was using a new strap. New strap is rock solid I can tell it’s starting to go when it’s starts dropping. I find I get about 6 months per strap, I ride 3+ times a week, I rinse it very well after every ride and run it through the washing machine once a week. I also have been

  176. Burgess

    Recently I have developed an irregular heartbeat when doing low-intensity running (Maffetone). Attempting to maintain a rate of <116 found my heart rate chest strap reporting huge jumps while I did not increase effort. Thinking the strap was shot, I am now using the Mio Link and find the same results. My question is how does the Garmin Fenix 2 record heart rate? Evidently the irregularity shows up in the Fenix as an increase rather than a skipped beat.

  177. Anthony R Lane

    I am currently using the heart rate monitor that came with my Kurt Kinetic InRide which is a re-branded Wahoo Tickr. I have been wearing it every ride since December and have been skeptical of its accuracy. I have tried the licking method, electrode gel, and wearing it dry. Despite all of those variables I still feel as though it reads too high. Even on very slow (10 mph) rides my heart rate is in high z2, low z3 (146-160 bpm)—which frankly, isn’t possible. Conversely, when I ride on the trainer my HR is always 20 bpm lower.

    I have also noticed that it will flatline on rides and have had it stay at a specific rate for up to 5 minutes with zero fluctuation.

    Has anyone else experienced perceived/presumptive inaccuracy such as this?

  178. Anthony R Lane

    I haven’t found a lot of success in the solution of using electrode gel to prevent spiking. Perhaps it’s just the monitor I’m using. Nor does it seem to offer more reliable and consistent readings than spit or sweat. Just yesterday I saw a max heart rate of 240 on a ride after using electrode gel. I’m on my third Kurt Kinetic montior which is just a rebranded Wahoo tickr. (link to kurtkinetic.com) I am very skeptical of their accuracy.

    I know heart rate is influenced by many things, but I cannot seem to get this monitor (or my heart) to stay in Z1-Z2 on very slow (12-15 mph) bike rides. I’m talking heart rate readings of Z3-Z4 when power readings are 50% of FTP. That just cannot be possible. I haven’t the ability to test the accuracy against and EKG when doing efforts, so none of this is proof…just speculation on my part.

    A couple other things I’ve noticed are unrealistic max heart rate levels as mentioned above and a generally huge discrepancy between heart rates while on the indoor trainer to those during outdoor rides…perhaps this isn’t a heart rate monitor issue, but more physiological?

    I’m thinking about switching to a Polar H7 or H10 in hopes of better accuracy or confirmation that the Kurt Kinetic unit I currently have is accurate and it’s my heart that is to blame.

    • Air-cooled runner

      If it is a soft strap, then disconnect one snap button and see if the HR drops to zero. If the HR stays at 240 despite the disconnection, then the fault likely lies in the transmitter unit, and NOT at the interface between electrode and skin.

  179. Derek

    I wear a Wahoo Tickr X which gives elevated readings for most of my run, around 170 and then may come down later in the run. However when I go out for a ride wearing the Wahoo it does not play up and shows readings I would typically expect.
    Any suggestions? Insights?

    • AndreaA

      Have the same unit. After almosT a year of usage, fails as you describe for me too… it gives odd readings for the first 5 to 10 minutes and then settles back. The Tickr has a twist, when it fails, it indicates a CONSTANT value (say… 160), then jumps to another and stays there for a while (see attached image). Then it starts to show a “normal” variation. I downloaded the R-R data but it is of no use. In a clear difference with Garmin units, Wahoo seems to record an “apparent” R-R…. ie, derived from BPM. When I analize a failed Garmin file, you can read part of the correct data in the R-R. For Wahoo it is impossible, it is a mirror of the derived BMP data.

      In the bike I use a CycleOps HR unit. I seldom use the Tickr, but fails much less….

      If you ask me, It is “signal/noise” ratio… When RR data grows, error (from heating the unit? static? contact?) reduces and the unit has better discrimination of the heartbeat.

      In the bike, there is much less movement.

    • Derek

      Thanks
      You are probably right.
      When i stop running my HR reading seems to go back to normal almost immediately, but then can get stuck at a reading for sometime.
      Probably time to buy something else as i have tried all the other suggestions!
      Thanks

  180. Jeff

    Used to have a garmin edge 500 and it would give me burned calories without the use of a heart rate monitor. When I would ride my 30 mile route in 90 minutes and average over 19 mph I would burn 2000 calories.

    Bought a wahoo elemnt bolt and it won’t calculate calories without using a heart rate monitor. I’m using a garmin soft strap monitor. Today I rode tge same route and it said I only burned a little over 1300 calories. You can see in my ride data that I had a few heart rate spike errors towards the beginning. During my ride when I would push it a little I thought my heart rate would have jumped higher than it did.

    Does my heart rate seem normal for the stats of my ride?

    Shouldn’t I have burned more calories?

    I’m 36, 6 foot tall, 166 lbs, and am a recreational rider.

  181. David

    My garmin HRM-Run is being picked up by my ant stick and my computer when using TrainerRoad, but no data was being recorded. Then I went on a run, my watch connected to the HRM, but no data was showing up on the watch. Changed batteries and licked the strap. Could it be the actual module is broken?

  182. Steve Meadow

    QQ – is it the strap or the transponder that is the “normal” cause of a failing HRM?

  183. Tom

    Wet the pads!! :) Yay. Thank you. I went through a major intervention with Wahoo and even sent is back and then got it returned. Still it would often not record a hr. Now you’ve solved it. Too bad Wahoo never told me about wetting the strap.

  184. Aldo Oreggia

    I have sunto sports I litle old but before works great now I start have the same problem
    When I start running my heart beat go up to 170bmp I stop many times if the problem is my heart lol but nop
    I wanna know if someone have the same problem with sunto ?

    • Not sure which Suunto you have but with any brand and model of belt you can get too high heart rate if your skin is dry under the belt. Some wet their shirts (sports shirts can generate static electricity that can give extra interfering electrical pulses to the belt) some wet the belt but I have found the absolute best way is to wet your skin under the belt as I show in my video: link to youtu.be

    • Jakub

      I have that problem as well. My feeling is that hr monitor catches my steps rather than my heart. It happens less when I run on softer grounds.

  185. Michael

    This helped a lot. However once I bought new Garmin strap and Hrm also a polar hrm. The polar hrm works with a app. I finally found out I had developed atrial fibrillation. My treatment was a defib shock and anti-fib drugs. I still need to see the doctor to clear me off blood thinners. I am back to normal except for being out of training for a bit. I found out this is more common then though. My point If you are having issues it maybe you. See your doctor. If you have atrial fibrillation and get shocked buy Heart Rate Gel because your strap sits at the bottom edge of the front shock pad. The shock tends to burn the skin slightly causing you HRM strap to not pick and wetting at first did not help.

  186. DHD

    These are all good suggestions but didn’t help me with my malfunctioning Suunto “Smart Sensor”. It would connect more easily with gel/moisture but still give completely bogus readings. What I found works well is to connect and disconnect it (starting then exiting from the activity on the watch) until it gives a sensible reading.

    My hypothesis is that there is some kind of adaptive filter, either in the sensor or in the watch, which can get thrown off by a bit of noise at the beginning of an activity and never recover.

    I will probably send it back to Suunto to see what they say, but it’s another thing worth trying.

  187. Marc

    Thanks for this very good post, because this can explain why I get abnormally high readings on my TomTom heart rate strap (such as 230 bpm). I was blaming this bluetooth strap and considerin a replacement, but the probable cause is static electricity since I always wear synthetic shirts. Will try to use dedicated heart rate gel now and see if this improves the matter.

  188. Matt

    I’ve been wondering something: When a strap goes bad, could I replace the strap with real ECG leads and sticky electrode pads (wiring them in to the connection points)? I have massive Hemiplegic Migraines. They can look like a stroke, seizure, and have all sorts or crazy symptoms. One of mine has Been some pretty wild swings in heart rate and conciousness/awareness. If I could maintain a good connection with one of these chest strap monitors I could get a good 2 weeks of data with each battery. This would let me have accurate data to show my doctors. Optical wrist sensors just aren’t good enough. I have a professional grade portable ECG, but it only gets 8hrs of battery life. That makes it hard to capture a migraine event when you are never sure when it is going to happen… So, any thoughts on how easily ECG lead wires could be tied into one of these monitors to replace a strap?

    • Robert Prater

      Matt – Why not try it? The female snaps that mate to the Garmin sending unit can be purchased at a fabric store so you could get a couple and make a strap out of elastic band material and just connect your EKG leads to the snaps. I also think that your EKG lead wires may be made of a small enough gauge to wrap around the male snap portion of the sending unit while it is still attached to the original chest strap. If the strap is not shorted between the two terminals it should work. It will obviously record heart rate but would not give you the granularity of a true EKG.

    • Matt

      Well I tried it, and it works like a charm. 24 hours, no glitches. I could have made the leads a little shorter, but I wanted flexibility in how I could locate it. It also doeant require you to have 2 leads on each side. Having 2 leads on each side means that if you are moving around and disrupt the signal from one, the unit doesn’t really notice. I have tested accuracy against an SpO2 monitor and still seems as good as the original strap, even with one lead on each side disconnected.

      I use a very comfortable, velcro ace bandage wrap to hold the unit in place. It works well and is much more comfortable for long term use than the original cheat strap monitor.

    • Matt

      I do wish I had a Garmin rather than a Polar. The Garmin Connect App is infinitely better. However, as far as I have been able to tell, you need to spend about $300 on a Garmin watch to use a Garmin chest strap with the Connect App. I’m not sure why this would be since even the $100 watches say they use ANT+ and Bluetooth, but it is what it is. I also wish Garmin Connect would allow 3rd party Bluetooth devices like the Polar chest strap, but I understand the financial reasons for not allowing this.

    • Fwiw – Virtually all Garmin devices released after Jan 2017 now support dual ANT+ & Bluetooth Smart (including the Polar strap).

    • Matt

      What Garmin devices are you referring to? I have a Vivosmart HR+ and Vivosmart 3. Both of these spec ANT+ and Bluetooth Smart, but as best as I can tell neither support external devices. The cheapest devices that are officially listed as compatible with the HRM-Run is apparently $349.99 according to the website listing. The older HRM-Dual has cheaper compatability options, in the $170 range, but nothing in the Vivosmart Series even though they have the hardware. And since none of Garmin’s chest straps are Bluetooth (all ANT or ANT+), nothing talks about being compatible with another Bluetooth device other than your phone… If you have actually figured this out, I would appreciate some help.

    • Basically anything besides the Vivosmart/Vivofit, since Garmin decided back about two versions ago to stop supporting HR straps there. Really weird as that used to be the selling point.

      The HRM-DUAL, as the name implies, is dual ANT+/Bluetooth Smart. All other Garmin straps are ANT+ only.

      So any Forerunner series, and Fenix series, any Vivoactive series, all support it.

    • devorah

      can you share how you made these connectors and add links to what you used by any chance??

    • Matt

      That first unit was made by just using some EKG leads that the hospital was going to throw away. They can also be found on Amazon. I cut the leads, soldered the wires and used some heat-shrink tubing on the connection. I had to do a little light Dremel work on the Garmin to let the leads snap on better. The right size button snap is the biggest issue. I used a knife and some pliers to open up the snap a little and make it work. This worked for a long time, but eventually the modified snaps that connected to the Garmin failed. I didn’t need to monitor much by that point anyway. I did eventually work on some new connectors with proper button snaps off Amazon. For that one I used an old USB cord for the wiring. It was a 2-lead instead of a 4-lead like my first one. I do think the 4-lead had more consistent/reliable data. I haven’t used it in a while but I will try to get some pictures. As for links, it has been so long I don’t remember all of it. My Amazon history may help. When I get around to getting pictures of the newer version I will try to remember to put up links as well. Maybe I will just go ahead an make a new 4-lead unit and document the design as I go. I’ve got a lot going on but I’ll try to get to it soon. Cheers.

    • devorah

      sounds good, thank you so much :) for responding.
      i know what thats like so if you need some time before getting to it i completely understand and am more than willing to wait untill your able to make and document the new 4-lead unit.
      and thank you for being willing to do it, its a huge help thank you.

  189. Ed Enriquez

    This might be an old post, bit still just as useful!! I was able to revive my HR chest monitor this AM!! Thanks Ray!!

  190. Twice in the last 2 weeks I’ve had runs with my Suunto HR strap that read my HR average in the 190’s and that my HR peaked around 229 bpm. I didn’t run any faster than normal, didn’t feel any different than normal, in fact, I’ve been feeling better than ever during my runs as I’m wrapping up week 17 of this training season. I’ve read of issues with the Suunto HR chest strap, but I also feel kinda dumb if I don’t consult someone or something else after seeing these big red flag readings. I’m pretty confident however that If I were peaking out at 229 bpm over the course of an hour that I’d notice it, be dead, be a humming bird, or all three perhaps. I typically shoot for a 140 hr or at least try and stay below 150 with no issues. However it is kinda concerning to see numbers like this. Any suggestions?!?!

    • @Mulkitez – can you swop straps with a friend to see if it is a strap issue or your body? I had similar weird readings without any symptoms that continued despite new straps etc. I eventually went to see a cardiologist and was told I had Atrial Fibrillation. Worth getting yourself checked out if you are concerned. It could well just be static, low battery etc and nothing to worry about.

  191. roger

    I had the issur described in the article. I learned from a Wahoo troubleshooting blog that you can reset the chest strap by installing the battery upside down for a few seconds. I was skeptical, but it worked. Will it work for other brands? No idea. Or as I like to say, “No-eyed deer.”

  192. Giuseppe

    I have trouble with Wahoo Tickr transmitter: I’ve changed battery two times and I’ve also changed the belt, but heart rate seems to be constant and not real, for example 47 bpm when I’m on a climb. Could I resolve with a new ANT+ / Bluetooth transmitter? Thanks in advance

  193. sile

    thank you, Sir. Very useful and pleasant to read, as usual.
    …and yes, it could be very frustrating to know you go as hard as you could and you only have 116bmp especially when you’re in the 50s range and problems could arise…

  194. Darlene Fjellgaard

    I have a tickr monitor. It does okay but when I’m working hard it doesn’t pick up until I stop so I don’t know where I am during the set. I’m doing H.I.I.T. classes. Could you suggest a resolution for this?

  195. Povl H. Pedersen

    Optical sensor on my M430 is unreliable. Does not like speed changes, starts way too low for quite some time. Helps a bit if I turn the watch around to inside of my wrist. I guess it detects a heartbeat once in a while (like every x of them), and then does some guestimation as to what happened in between. I have pretty bright skin.

    Now my older CooSpoo (BT only – looks like H5 – H8?) is acting up, especially with intervals, or speed variation. Seems like when cadence goes up, HR just runs up way faster than it should going to 210-220-ish. Sometimes it just goes to 185 before going back to 150-160. Sometimes it makes random peaks at 200. It is absolutely unusable. Seen 229 max.

    So I have now ordered the Polar H10. Supposedly one of the best out there. And I went for the H10 over H9 because of the onboard memory, which I assume will help in case of connectivity issues. And in general it is considered one of the best. Only 20% or so price difference. And the Accelerometer might get use at some point.