Aside from a light-reflecting text logo, the Whoop 3.0 wristband (free with a membership that begins at $30 a month) is nearly indiscernible from a fabric sweatband. There’s no screen for real-time tracking, certainly no intruding vibrations or sensors and no surprising alerts. As such, this couldn’t replace an Apple Watch or everyday time-teller. That said, everything you do—working out, recovering, sleeping, walking to work, yoga, meditation—is tracked automatically and uploaded to an adjacent app as long as you keep the band charged and on—something easy to do as the band holds five days worth of battery and can be replenished while you’re wearing it.

Using your heartbeat and heart-rate interval as its key measurements, the Whoop band calculates your overall fitness by monitoring your strain, sleep and recovery. “Strain will reveal how your body is responding to things like stress, travel, and work,” the Whoop site explains. High intensity workouts, on Whoop’s strain scale of 0-21, clock in above 18. Walking to work would fall somewhere been 9 and 15, depending on your pace. When testing ours out, we had no problem getting above 10 at any given moment.

The most impressive aspect of Whoop’s offering is its ability to track recovery and heighten awareness regarding your overall wellbeing. Recovery, on Whoop’s scale, is measured from 0-100. For optimal performance in the next day’s workouts, or even one later in the same day, recovery numbers should reach the green zone—around 79% or higher. Yellow and red zones denote 68% and 15% respectively.

The numbers and their respective zones may vary based on your personal fitness level, though. Your suggested exertion level will be revealed in real-time based on your recovery level—if Whoop doesn’t believe you’re ready for an intense workout, it’ll lobby against beginning one. Insight into how sleep debt heightens the likelihood of injury and lessens your ability to train properly backs up this advice.

A personalized Sleep Coach tracks your night’s sleep, the amount of sleep you need based on the day’s workouts and the following day’s expectations, how many disturbances you faced through the night and your REM. Your resting heart rate is a vital measurement here as it’s also a key marker in your overall health. Whoop emphasizes quality, efficiency and consistency when describing sleep—the trifecta of markers will not only help you improve your ability to rest but they’ll also make you hyper-aware of how you’re treating your body. Waking up tired or sore—the app also prompts you to self-report feelings of soreness, tiredness, readiness—can be traced back to something you did or did not do: heading to bed at the right time or overworking your body, for instance.

In our experience, as we’re far from a professional athlete (though plenty—from Michael Phelps and Neen Williams to Marc Gasol and LeBron James—do wear one), the Whoop 3.0 didn’t shame or pity our habits. It cleverly adapted to them and worked to drive us toward our peak (and promote overall health). Even if our most strenuous workouts were an hour-long bike ride or an afternoon worth of pick-up basketball, Whoop measured our strain just the same—and offered insight into how we could better recover, rest and perform, even if our performance wasn’t high-stakes by any standards. As long as our recovery score exceed our day strain (the two are graphed for easy reading), we were doing well by it.

If our night’s sleep began at 8 PM one night but at 3 AM another (as irregularities occur for everyone), we weren’t scolded. We were given a score and that score could be undone if we actively made other health-forward decisions. If we skipped a high-intensity workout, we could report our soreness and opt for walking home rather than taking public transportation. This wearable is perhaps the most all-encompassing health and fitness tracker as it presents your numbers with both seriousness and ease, rather than gamifying them and subsequently fading out of your routine.

Images courtesy of Whoop