[Closed] Wrist based H/M monitoring, does it actually work?

In my experience they’re not very accurate. I’ve got a Frnix 5S and use it merely as a guide

It depends on what you are doing.

Generally slower to pick up changes so less use for interval training and if you are doing something with lots of wrist movement (no not that but mountain biking for example) it will be less accurate.

In my experience they only seem to work when you are not actually exercising. So they are ok for testing your resting heart rate, but once you start going above 100bpm it gets increasingly inaccurate & doesn't seem track Zone 4/5 effort at all.

It works for some people including me, most of the time, but better for running than cycling. Chest straps also have problems for me, especially cadence locking when running. Just due to bounce I think. Overall mine is better than the chest strap was.

I don't have a problem with mine (Fitbit) as it appears to track my heart rate consistently (ie, I get similar results when I repeat exercise such as spinning classes and ParRuns). I have no idea how accurate it is but the data seems pretty consistent with what I would expect and I am not relying on it to be that accurate.

IME they work fine for steady state training. Most of my Ironman training is long & slow in z2 with very little in the way of intervals. For this is works fine - running in my z2 as indicated on my fenix 3hr is comparable effort, hr & pace as to what I recorded on the old 310xt with chest strap.

Start to do a hard effort and it lags behind the chest strap.

The instruction manual on my Polar M200 recommends that when I'm about to start an activity, I should move the watch up my wrist higher than usual and tighten the strap a wee bit more than usual. I find that this gives me a more believable* heart rate, than if I forget and have the watch lower and looser on my wrist. Like someone else said though, it is just a guide. As long as you find you're getting consistent results, it doesn't really matter, does it?

*Believable in that at times I can be completely blowing out my arse and my watch claims my heart rate only 130bpm....more like 290 matey!

Some wrist HRM are better than others. And they work well for some people, but not others.

Try the watch in different places on your wrist. I find it works best with the watch a bit further up the wrist. And with the watch/sensor on the inside of your wrist.

Also the strap needs to be quite tight. Almost too tight to be comfortable.

I've a Polar 430 "watch".  There's a bit more lag as HR changes but that aside, it gives pretty much the same results as a chest strap (I've used it alongside chest strap on the MTB and the turbo) - and the GPS seems more accurate than my Garmin 810 too, FWIW

(agreed on the "fairly tight and well above the stickyoutywristbones")

Have you compared the chest strap readings with taking your pulse?

I've got an Apple Watch, and I find it's pretty accurate, even when compared to a Garmin chest strap.

The chest straps can go a bit funny if the battery is on the way out...

Apple Watch 3 seems realistic (i.e. 50-60ish when just sitting, 180+ when running hard!) but not compared it to a chest strap for accuracy. Certainly doesn't seem way off like others are suggesting above.

i find a lag when doing intervals.

i find a lag when i climb a hill - i climb the hill at X - about half way up it goes x+ 30 - then about half the way down the other side its back to X

dont see that with a Chest strap.

garmin 735xt wrist monitor.

I only use mine to confirm I'm alive.

They're reasonably accurate certainly no worse than a chest mounted one. To get a good heart reading from an electronic device of any perfect accuracy you need to still at the time. So as a guide they work fairly well.

I find mine works fine for running or steady road riding, but anything that involves a lot of vibration, or lots of movement, it goes to pot, so I wear the strap.

Apple Watch one seems OK, although I mostly use it for running and I'm not doing training in zones or anything. I do up the strap one notch tighter and that seems to deal with the random dropouts.

My Apple Watch works fine when compared to my chest strap one for my Garmin cycle computer. Can be a little slow to pick up sometimes but the lag is only seconds and it generally agrees. I use it for my spin classes which mixes up high intensity and low intensity workouts and it registers hear rate changes no probs in relation to the changes in exercise intensity.

Talking of HR and Watch - anyone recommend a watch app for working out / exercising to intervals?

For the OP - the Watch seems consistent but I'm only looking for trends and comparison rather than all out accuracy so haven't compared it.

For the OP – the Watch seems consistent but I’m only looking for trends and comparison rather than all out accuracy so haven’t compared it.

I have with an ecg machine costing several 1000s. It was spot on when still and both crap with too much motion.

I've used 2 Mio wrist based HR monitors (as well as traditional chest ones) and find them pretty accurate and consistent.

They do sometimes miss very fast changes in HR and take a short while to 'lock on' again, but that is easily outweighed for me by the improved comfort and convenience.

Fr735 xt owner. OHR only good for outdoor activities. Inside and I use HRM strap. It's the amount of sweating. Inside my arms are a lot sweatier (squash& football) which seems to upset the optics. I've tried tightening wrist strap and wearing wrist band over top, but doesn't really help.

Not wrist based and a tiny sample size, but:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1478836/

I can't have tight wristbands, so I use a forearm HRM. Seems to be about right, picks up changes fine for looking at workout stats. I'd probably suggest it's more calibrated to 50-150 than anything higher though.

decent enough for me.

From what I read when I got mine they work on power saving plans most of the time, so if your HR is the same when it checks in 1 min it will check again in 2 mins etc, this means it can get the longer battery life and still have trends, if the HR moves it cuts the sample time back down again. Generally this makes them bad for intervals and stuff like that. Not sure how it adapts when you are using them in specific activity/monitoring modes though

For me it's still more accurate than chest strap which never made a consistent contact for me and kept dropping out.

My Garmin 235 is fine for resting hr but crap for active. I've done a few rides logging both on the watch and on a bike gps with proper hr chest strap. The watch isn't close to being accurate. Found similar with other watch hrms but if course a relatively limited sample.

"For me it’s still more accurate than chest strap which never made a consistent contact for me and kept dropping out."

Are you a gorilla

Not quite but they never held a decent connection for me, when I lost the last one I never bothered to replace it. The watch is on all the time, makes life a lot easier

Most proper and thorough tests on wrist monitors I've come across seem to say they are generally accurate until you start to exercise with some amount of vigour.  So daily/sleep monitoring is OK, but not workout stuff.

My Fitbit matches my chest strap for walking. Cycling and swimming.

I am pretty white and not hairy which apparently makes it easier for the sensor.

I have had a Mio fuse/slice, and got a vivoactive 3. The Vivo wins out.

I've compared both to the HRM strap on the same MTB ride. They lag and don't reach peaks as accurately.

To improve results; wipe wrist and sensor and do up tight further up wrist.

But the nature of being bashed about works against them.

anyone completely trust their wrist based data ?

Not completely, no. As above, you need to tighten the strap a notch to stop the watch moving around, slightly uncomfortable to wear all day like that. If I was training seriously, I'd use a proper HR monitor, not a watch.

I find mine works well enough for walking and running but it really struggles with cycling.  I think it might be the wrist position and wrist movement of cycling.

I use a Mio Go. I've found it's just as accurate as a chest strap for cycling and running and responds fine to intervals. I have to wear it slightly tighter than I would wear a watch but not uncomfortably tight. It also works better on my right wrist for some reason. Only issue I have is the battery life which is 5 to 6 hours so no good for longer events like sportives.