WHOOP 4.0 Initial Accuracy – Is it Accurate in the Gym?
For my WHOOP Band 4 Review later this year I’m teaming up with Hunter from the FitGeatHunter YouTube channel, he’s one of the very few YouTubers that do more serious gym/Cross-Fit heart rate testing across a range of devices and a range of exercise types. He’s had his WHOOP 4 for a couple of weeks.
I don’t produce videos or do much gym work/Cross-fit, whereas Hunter only does YouTube and Cross fit. Seems like a pretty good match to me! And he’s a nice guy and a great presenter!
In addition to what Hunter is doing in the gym, I’ll be adding my swim, bike & run accuracy results once my WHOOP 4 arrives.
These first tests from Hunter are all with WHOOP worn on the wrist, which is typically a common, but bad, place for optical HR devices and even worse when lifting and twisting in the gym. His subsequent tests will use the upper forearm and bicep, the latter should hopefully produce good to excellent results (edit: that seems to be the case). For some of my tests, I’ll probably also wear WHOOP on the underside of my wrist as I seem to get better results there, although my aim for my own stats will be to always wear it with a WHOOP arm sleeve during exercise.
1. WHOOP on the Wrist in the gym
Here are some results from earlier tests
And here are Hunter’s first impressions based on his first tests. These results weren’t so good but the video is entertaining and worth a watch!
Take Out
It’s early days and early day accuracy with most new optical sensors is not great when worn on the wrist. Less great when also used in the gym!
There are some promising signs of accuracy from these early tests by Hunter in the gym and I’m hopeful that I’ll see much better results when I’m out running and cycling in easier conditions for the tech.
However, WHOOP is becoming the de-facto, go-to Cross Fit tech tool of choice. The rigours that Hunter is putting the WHOOP through are precisely the ones where WHOOP needs to focus on improvements rather than trying to appease triathletes like me.
Hunter’s use-case for WHOOP places more emphasis on assessing the accuracy of the time in the various HR zones. This is particularly important for determining strain, which is WHOOP’s thing. People like me, and I suspect dcr, are more interested in WHOOP being correct at any given time and so useful for regulating effort level over longer workouts. I guess you can obviously argue that if it’s correct at any one second then it will be correct for the zone-based calculations! I’ve usually found with WHOOP (v3 and before) that it was generally sufficiently accurate to determine strain but less reliable when it came to being used as a pacing tool. I’m hoping that will be improved in v4.
Note: Using heart rate is not a great way to determine the true strain from, for example, lifting heavy weights. At least it’s not for me. That said, WHOOP’s acquisition of PUSH earlier this year promises a market-leading platform for gym-goers worldwide. PUSH seems to be able to more correctly assess the strain during strength-based workouts by working out the number of reps that each weight was lifted, and so counters the inaccuracy of relying on HR for this kind of workout. #Exciting.
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Why is he using the band on the wrist? Using the sensor on the upper arm or in the forearm is feasible and has much better results in general (in my case, I’ve done gym workouts with the OH1, the Scosche – gen. 1 – and AW4-AW6).
HR on the wrist for gym workouts is going to be crap even with the best sensor on the market…
he is testing all those wear-positions, which i think is the correct thing to do.
then you can compare like with like. eg wrist for apple watch vs whoop on the wrist
then bicep for OH1/verity vs whoop
Ah ok, my bad! I didn’t watch the entire videos, only consulted the graphs…
From the article I assumed he was testing only from three wrist… testing all the locations is the right procedure indeed, as the product is intended to be worn in any of them.
The video clearly states why he did it……He states this is where all the crossfit ppl are shown wearing it. He also said he is going to test it in other places on the body. Then at the end of the video he says the whoop 3.0 got better reading on the bicep. Which is where I think he is hinting to wear it, but then also wants you to come back and watch the bicep 4.0 video later down the road
yep, something like that. he’s partway through the bicep tests and the results that he’s shown me are very good. which is what i would expect-cum-hope
thanks for the whoop code still 9 to 11 weeks away for me….thank you guys for your work on putting all this info out there
ty for coming, yes mine is still 3-5 weeks but i think it suddenly updates and they send it quickly from what i’ve seen elsewhere. so i’m hoping it’s this month.
Got my 4.0, along with a biceps band, which is the only acceptable wearing option me thinks for anything other than steady state runs. Took it on a run, indoor bike with some surges, and functional training today that included bodyweight exercises and kettlebells.
In a nutshell, very, very good OHR quality and great improvement over 3.0.
Both average/maximum HR matched to a beat (I tested WHOOP connected to COROS vs HRM-Pro connected to Garmin), but more importantly the HR matched throughout the session, with a bit of a lag, no more than 8-10 sec, for strength. But I’ve seen similar lag in OH1 and Verity Sense for anaerobic/alactic loads, so I’m not holding it against WHOOP. Very hopeful so far.
(Strangely, the heart rate reported inside the WHOOP app, when you add activity there, differs in terms of average numbers compared to what’s shown by the watch connected to the same band via BLE. I don’t know how the WHOOP is doing its averaging, but it is still 2-3 beats below for the same time series that produces expected results when captured/averaged by the watch.)
well, that’s good news
Oh yes……4.0 came today and compared it apples to apples
polar verity Max HR 187 bicep
Whoop 4.0 Max HR 187 bicep
5K 22:54
Avg HR 141 polar
Avg HR 142 whoop
Total time 30 minutes
Whoop did make me faster. I am happy with my results @ 52. I felt like death at one time and seen a midget stripper flash before my eyes.thank you mr runner man…. whats a good choice for a strickly treadmill runner as far as shoes Hooka to cush, ON too stiff, nike meh, brooks my fav so far.
ha ha , yes very good!
i’ve heard other stories of good bicep performance on whoop4. (i’d expect/hope for that)
tech really does make you faster: try this https://the5krunner.com/2021/04/11/a-garmin-makes-you-3-faster-controversial-science/
there’s also a study somewhere that says under-reporting tech makes you EVEN faster !
thanks for the read, it is interesting and well written
well I have never really liked running as cycling is my goto sport but I got burned out racing on zwift and took a massive hiatus and took up running. Well Wogging Walking slow jogging. This process has been a battle and the whoop 4.0 is a serious motivation machine. It makes me want to test more stuff….
Back of the bicep today
10 KM @ sub 47
182 max HR both
166 polar veritas sense avg HR
165 whoop avg HR
The whoop is as good as the polar veritas sense so I am super happy. This is worn on backside of the tricep. I think I found my happy spot. No idea why so many degrees of variation in readings, but hell yes I got a good one regardless.
Sorry I missed these! Yes testing in three places: wrist (complete), bicep, then forearm. Bicep is excellent and should have the review out later today!