WHOOP HR Accuracy – Again


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11 thoughts on “WHOOP HR Accuracy – Again

  1. Been supporting this blog for years, generally great work and appreciated. But dude it’s annoying to put content behind a paywall, you will lose readers.

  2. Hey Stefano,

    thank you for your ongoing support and I’m sorry that you find the paywall annoying. the content IS visible to logged-in supporters (thank you) and I will make this content visible in a few days if I remember.
    I’m still at a loss as to which method I should use to keep everyone happy all the time…adverts are annoying, optional donations are clearly annoying, affiliate commissions are only not-annoying when they link to the lowest possible deal from each readers’ favourite store (I do try my best there)…and so it goes on. Only a tiny percentage of people click on the supporter links before they go on to buy something from Amazon or one of the other linked sites…

    Perhaps the least annoying way is for me to stop my other job and spend 5 days a week working for free on this?

  3. Re: the paywall, it got me to subscribe today. I get a lot of value from your page and I had been meaning to subscribe for a while, so this was a good reminder for me. Agreed that the options to monetize are all probably annoying in some degree to readers, just how it is, and I understand you can’t do this full time for free. I’d MUCH rather support you and thus support more content.

    On to Whoop, I’m about 3 weeks in and debating keeping it. I’m a pretty good candidate for optical HR, Garmin/Polar work fine for me from the wrist, and my Scosche Rhythm 24 works great for strength training.

    Whoop seems to do a reasonable job on the wrist when running. Maybe a few weird numbers at the beginning of the run sometimes, but mostly inline.

    Where I’ve been disappointed is the accuracy on the bicep when strength training. I’ve been comparing it vs the Scosche and vs a Polar H10 as a baseline, and the Whoop seems to consistently cut out peaks in HR. For example, after a set the Scosche would have my HR peaking around 132 and the Whoop around 121. This is after a set is complete and the Whoop never catches up and reports those peak numbers.

    As I’ve been trying to get better numbers from the Whoop. I’ve also found the position on the bicep to be incredibly sensitive. For pull ups, outside of the arm closer to the bicep seems best. But this position is pretty bad for pushups, I need to go closer to the tricep side. The Scosche seems largely unimpacted by position, I just keep it in the middle of the outside of my arm.

    I really like the concept Whoop has here, but the fact that an hour and 15 minutes of strength training got me the same strain as a 25 min non-strenuous walk makes me question the validity of the results I’m going to get overall. I’m also not a fan of the singular HRV number, would rather see more detail like Polar or Biotracker provide.

    1. Hi Jason, thank you for the support and for this feedback.

      H10 Baseline in the gym: I’ve not tested bicep usage. I noticed one on DCR’s bicep recently so he might have a post coming on just this subject.
      What you say seems quite plausible. ie bicep related exercises might struggle with the whoop on the bicep (or other oHRMs on the bicep). Maybe you could answer me a question here…WHY do you want accurate HR in the gym? in the sense of ‘what do you do with the data?’…the reason i ask is that i simply can’t get my hr high enough in the gym to feed through ANY meaningful TRAINING LOAD type level of HR. HR is not really measuring the work you are doing nor the impact on your body (perhaps there are indirect inferences?)

      You give the example comparing to a long walk. Yes even with a chest strap that is the same equivalent stain that HR would show for me (near enough) ie both would be pretty much zero.

      However if whoop or anyone else use a motion sensor and reps WITHIN A STRENGTH WORKOUT SPECIFIED BY YOU to somehow score reps and infer a muscle load , then maybe that’s possible ish. perhaps. could be.

      Scosche – yes that is where I would wear these by default.

      1. Well, presumably there’s a difference between a spike of HR to 140-150 on heavy lift or plyometric exercise like kettlebells or box jumps vs a cut-off at 115-125 if HR tracking is off. If we go by Firstbeat/Garmin methodology, for the former you gonna get a nice anaerobic effect. For the latter you gonna get bupkis, which is quite a bit upsetting for any self-respecting data-driven OCD type. Not to mention, more accurate HR, with no peaks missing, will imply higher strain. Which is better than lower strain, even if not as good as some measure that would take in not only an average cardiac load from the session, but perhaps a measure of how it varied.

        1. agreed. I don’t think my HR has ever gone above 120 in the gym (except on a treadmill 😉 )

          140-150 would be my zone 2 (approx)
          a simple TRIMP-based training load would say that was a mild aerobic effect if only for a few minutes. UNLESS it treats different sports profiles differently.
          I can check with FB and see what they say.

      2. Before I got the Whoop, I didn’t really care about HR in the gym. I’d still track it, as I could somewhat infer if I’m working hard or slacking by the peaks, but I never look back at a strength workout recorded on my Garmin. With Whoop though I’ve got a strain goal that I’m trying to hit, and unless I want to double my running miles or ditch the strength training for another form of cardio, I’m not finding it possible hit. I guess cardio strain vs muscle strain, but I feel like the strength workouts do put more of a strain on the body overall (muscle, CNS, whatever) than what Whoop is giving me. And I keep thinking if Whoop was seeing 30 sets peaking 10 to 12 BPM higher, would I be getting a more reasonable strain number from the workout.

    2. Are you using a biceps band for your WHOOP while strength training? If not, anything on the wrist or around will be garbage. And I have a feeling that not all biceps bands are equal, especially if the said strength training exercises involve mmm… biceps. I get better accuracy with older, stretchy bends than, say, an impact sleeve on all curls and cleans. Not seeing this difference for non-bicep heavy exercises.

      1. I am using the bicep band. I’ve tried all sorts of arm positions on the upper arm and forearm, but can’t get good consistent results.

        I do think the strap on the Scosche is better. It’s wider and attaches to both ends of the HRM vs the Whoop clasp where the band is essentially attaching at the same end and then lying over the HRM.

        What I like about Whoop is how it takes into account everything. But the other side of that, is if I think it’s giving me not that great numbers for one thing (strength training) is that then throwing off everything?

        1. yes the scosche is a better sport-specific band design. however you probably wouldn’t wear the scosche 24×7 and that is where WHOOP came in. they could still improve the hinge but that’s another story.

          Q: “is that then throwing off everything”
          A: No probably not. but it depends on the volume and nature of gym work and your target sport/race.
          yet clearly MUSCLE LOAD is impacted in some way. I’m just not sure myself who does this piece of the jigsaw well.

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