At rest it would randomly read 2x my RHR and during even basic movements like painting it would jump to my HR max. Fundamentally all the subsequent findings were then useless. Here’s a better representation of how close WHOOP’s HR data was to the chest strap. I should point out, however, that the Wahoo app only recorded one HR event every four seconds, whereas the chest strap/Apple Watch combo recorded an event every second.

To meaningfully unfold the story behind the numbers, WHOOP has a web-based app companion, which is an extension of your app. Initially, you’ll have to unlock these types of reports by simply using the app and the wristband consistently for 7 days first. Eventually, you’ll unlock your monthly performance report. This is where the web app comes in handy; it lets you see the changes month to month. The format you get in the app is PDF, which is less than ideal, but like any new product — you got to start somewhere.

So far I have no HRV data, and I wouldn’t trust it since it can’t even calculate an accurate HR. I have contacted Whoop support and after a couple weeks of lost time they are supposed to be sending me a new unit. I think even being able to add when food is consumed whoop for weight loss and comparing how it made you feel physically to your WHOOP metrics could also be super insightful. Perhaps that’s because I love to eat, and I love to see how the food affects my body. Or perhaps I’m just ultra-picky about my self-quantification devices.

Difficult to measure factors including the composition of your microbiome – that is the ecosystem of bacteria that live in your digestive tract – influence the proportion of food calories that actually get absorbed. What this all means is that, even if you weigh every gram of food that you put in your body, you couldn’t possibly count your caloric intake with smaller than a 20% error bound. Those 2000 calories you believe you consumed could easily have been 2400, an error bar approximately the size of a McDonald’s Double Cheeseburger. Over 100 years ago, Arthur Harris and Francis Benedict came up with the “Harris-Benedict Equation” for predicting BMR from height, weight, age, and biological sex. While small changes to these formulas have been made in the century since, they still largely remain intact.

Making sure you have a snug fit may improve the accuracy of energy expenditure. While trackers are definitely fun and trendy, they still have a way to go. However, that doesn’t mean you should rule them out as a way to reach your weight-loss goals. I wore them at the squat rack, when cooking in the kitchen, and to the movie theater to see Beauty and the Beast. I only took them off during showers, although Withings is water resistant to 50 meters deep. I tapped the glass display and could cycle through all of my stats.

When I first heard the name “Whoop”, my brain naturally responded with the phrase “there it is.” My brain is a little off since that song actually says “Whoomp! There it is.” But, hey, thank you, Tag Team, for conditioning my response regardless. From my experience, it actually does drive it a bit as well.

For reference, two days ago I walked a couple of miles, then did 30 minutes on the Peloton that left me walking on noodles, and my overall strain was 8.6. What I found frustrating is that pushing up the Strain score is, well, strenuous. Trying to push the Strain score gave me a bit of a maybe-I’m-not-good-enough-to-play-blades feeling. I would do my usual workout on the Peloton or go walk a round of golf and the Strain score wouldn’t jump like I expected. Speaking of battery, a fully charged Whoop will make it four or five days before needing to be recharged. When you recharge it, the battery slides on the unit and charges it while you continue to wear it.

It tells you how many hours of sleep you got, how many hours you needed, how many hours were spent in the REM cycle, the number of disturbances you experienced during the night, your heart rate, and more! Then, after all this data has been considered, you are assigned a performance percentage for your sleep. Prior to that I was taking a morning HRV reading using the SweetBeatHRV app. Every once in a while I will still do a morning reading with heart rate strap just to see if it correlates with the whoop. The trends are always similar, but the actual numbers are different.

Each day you get an optimal strain score or the day depending on your recovery score. You’ll know exactly how much to push your body without overdoing it. You’ll even get a little haptic vibration on your wrist when you’ve reached your optimal strain during a workout, which is a nice feature upgrade compared to the 3.0. Studies have shown that fitness trackers are relatively accurate in tracking and recording activity, however energy expenditure still proves to be a relatively challenging variable to quantify.

If the data coming in is garbage, what is the value of all the analysis of that data? Having insights into the quality of my sleep, including what factors influence it and the condition of my nervous system, helps me make better decisions throughout the day. I’m a serious fitness enthusiast and I wear WHOOP to help me improve my overall health and well-being. We already know that WHOOP is incredibly accurate when the conditions are right, and slow-wave sleep is the perfect condition to take RHR and HRV measurements. Based on my understanding of how the “sleep need” figure is calculated, and my experience with the “sleep coach,” I don’t think the recommendations are unrealistic at all. What most people don’t understand is that sleep debt is accumulative.