If you’re a sports fan, you may have noticed athletes including Golden State Warriors point guard Stephen Curry, Houston Texans defensive end JJ Watt, and tennis phenom Maria Sharapova wearing the same, screenless band on their wrist. It’s a health-monitoring device called the Whoop Strap, and none of these athletes are paid spokespeople or investors. Originally designed for professional and college athletes, the Whoop has evolved since its 2015 debut into a consumer-friendly device and service meant for anyone trying to set and accomplish a health-related goal.
The third-generation Whoop Strap (free with a monthly membership) goes beyond fitness tracking to monitor your daily strain, sleep, and recovery, and its companion app offers personalized coaching to help you optimize your training and shut eye. Its subscription-based pricing model makes it an ongoing investment, but the Whoop becomes more useful over time, offering data-packed performance assessment reports every week and month that can help you uncover trends and analyze your progress (or lack thereof). So while it’s pricey, the Whoop Strap is a compelling alternative to a traditional fitness tracker if you’re looking to improve your sleep and train smarter.
A Different Type of Tracker
The Whoop Strap has a different pricing model than most of its competitors: Instead of paying one lump sum for the hardware and getting its accompanying software features for free, as is customary with most fitness trackers, here it’s the other way around. The company offers its basic black wristband for free with the purchase of a membership, which gives you access to the app. In other words, the Whoop Strap isn’t just a one-time purchase.
The company offers three pricing options: $30 per month (with a six-month commitment), $288 per year (which works out to $24 per month, offering a $70 discount compared with the monthly membership), or $324 for 18 months (which breaks down to $18 per month, offering a $216 discount compared with the monthly payment plan).
A spokesperson told me Whoop switched to a subscription model in 2018 to give more people the opportunity to try the service. The company offers a 30-day return policy, so if it doesn’t meet your expectations, you can return it within a month for a refund (minus shipping costs). The company justifies its membership fee through regular app updates, offering timely features like COVID-19 tracking. We’d like to see it add compatibility with Apple Health and Google Fit in the future, as right now it only integrates with Strava and TrainingPeaks.
The strap features a stretchy knit band lined with sweat-absorbing filaments and an anti-slip rubber grip, and it’s safe to wear in the ocean, pool, shower, and sauna. It’s light and comfortable to sleep in, measuring just 0.375 inches at its thickest point, though at 1-inch wide, it takes up a fair amount of space on your wrist, meaning you probably won’t be able to wear it alongside a watch. Whoop says it designed the strap to be unobtrusive, but in my opinion, the black-on-black Onyx model I tested stands out like a sore thumb.
If you’re not a fan of the all-black look, Whoop sells accessory wristbands in many other colors, ranging from $25 to $110. I like the look of the Lux Knit bands, but they’re the priciest. Whoop also sells bicep bands if you prefer to wear the tracker higher up on your arm. You can get the device engraved with your contact information, medical alerts, or a special message for an extra $25.
The Strap has a built-in battery, and comes with a charger and external battery pack that you can slide onto the tracker while it’s still on your wrist. This means you really never have to take it off, allowing for continuous monitoring. Just keep in mind that while the Whoop is waterproof, the battery pack isn’t, so don’t wear it in water or slide it onto a wet strap. I always remove the Whoop when showering anyway, since the knit band takes a while to dry after getting wet.
In testing, the Whoop’s battery lasted just over five days, as advertised, and it only takes about an hour to fully charge.
Setting Up the Whoop Strap
One of the things I like about the Whoop is that the company offers all members a 30-minute onboarding call with a live representative to get acquainted with the device and its main features.
Setting up the Whoop is very simple; its companion app walks you through the process. Just download the Whoop app (available for Android and iOS), allow Bluetooth access from the pop-up so the strap can communicate with your phone, and create an account. From there, the app begins searching for your strap; when it finds it, tap Connect and accept the Bluetooth pairing request.
At this point, the app offers instructions for attaching the strap to the tracker, tightening it to fit your wrist, and closing the clasp. For me, this was the hardest part of the setup process, but after some trial, error, and frustration, I eventually figured it out. The Whoop should be worn one centimeter away from your wrist bone, and tightened enough so it’s hard to get a finger under the strap. You want to make sure the sensor stays firmly planted against your skin and doesn’t move around much.
The Whoop features three tiny LED lights on the side, which stay off by default but illuminate when you double tap the top of the device to indicate its battery level (you can also just open the app any time to see its exact battery percentage). Three solid white lights means it’s fully charged, two means it’s at around 60 percent, and one means it’s at around 20 percent. When the LED shines red, it means your battery is down to 10 percent or less. Double tapping the top of the device also automatically turns on Bluetooth, which you only need to do if you ever have trouble connecting, though in testing, I never experienced any issues.
After connecting to the strap, the app asks you to input some information about yourself, including your name, birthdate, country, state, sex (there are options for male and female), measurement units, height, weight, and current fitness level. You can optionally enable notifications, which I recommend so the app can inform you when your data is ready for review.
Quantifying Strain
The Whoop app is well organized and intuitive. It presents your data in a way that’s easy to understand and offers actionable recommendations to help improve your sleep and training.
The app has four main sections: Overview, Strain, Recovery, and Sleep, which you can navigate between with swipes left and right. The Overview section gives you a quick snapshot of your daily metrics, including your recovery percentage, total day strain, heart rate variability, calories burned, sleep duration, and any tracked activities. From the Overview section, you can quickly start recording an activity, or journal anything about your day.
The sleep data is self-explanatory, but I initially had a little trouble understanding the strain and recovery metrics. Both are a key part of the Whoop experience, so you’ll get to know them very well after using the tracker for a bit. I’ll go into recovery in the next section, but for now, let’s discuss strain.
Measured on a scale of zero to 21, strain indicates your cardiovascular load, or how hard you’re working. The Whoop measures your strain for each tracked activity, and over the course of each day overall.
The strain metric is personalized based on your heart rate data, and accounts for differences in individual fitness levels. The Whoop first determines your maximum heart rate, then uses that number to establish your personal heart rate zones. It then monitors the duration of time you spend in each of your heart rate zones to calculate your strain.
So if I run a 5K, I can get a totally different strain score from someone else. If the 5K is easy for me, but difficult for another person, my strain score will be lower, even though we traveled the same distance.
The app explains that “all out, near maximal workouts” are considered 18 and above, strenuous workouts are 18 to 14, moderate workouts are 14 to 10, and everything below 10 represents light or minimal activities. After workouts, I’m always excited to see my strain score.
After a one-hour indoor SoulCycle session, the Whoop said I burned 405 calories, reached average and maximum heart rates of 136bpm and 171bpm, respectively, and earned a strain score of 12.8.
In contrast, after a gentle, one-hour yoga session, the Whoop said I burned 92 calories, reached average and maximum heart rates of 90bpm and 144bpm, respectively, and earned a strain score of 4.8. The app says that low-strain activities like yoga promote recovery. As a yoga teacher, I already know this, but I love that Whoop offers education and encouragement like this.
An interesting observation I’ve noticed is that out of all the activities I do, running is the most straining on my cardiovascular system. I’ve been wearing the Whoop for a little over a month, and my highest strain score for a single tracked activity was 14.8, earned during a 36-minute run with my dog Bradley.
The app also calculates your total daily strain, taking into account tracked workouts and all other heart rate data. This can help you determine how non-workout activities contribute to your daily strain.
One of the things I like about the Whoop is that it gives you a daily optimal strain target, based on your recovery. As I’m writing this, for instance, it’s almost 2 p.m. and I’m sitting at a total day strain of 9.4 with one tracked activity (a 30-minute indoor cycling session, for which I earned an 8.3 strain score). The Whoop says I’m already at a balanced level, but recommends I build an additional 6.6 strain into my day to reach my optimal target of 11.2. Meanwhile, according to the app, “going above 15.2 will promote fitness gains but may diminish your body’s ability to recover.”
Tracking Your Recovery
Recovery is another metric you’ll become very familiar with when using the Whoop. Measured on a scale of one to 100 percent, your recovery score indicates how well prepared your body is to take on strain. In other words, it’s how well your body is able to return to its baseline following stressors like exercise, illness, and stress.
The duration and quality of your sleep plays a big part in your recovery, of course, but the Whoop goes beyond just tracking your shut eye. When calculating your recovery, it also takes into account your heart rate variability (HRV, or the amount of time between successive heart beats, a measure of your nervous system activity), resting heart rate (RHR), and respiratory rate (the average number of breaths you take per minute over the course of the night).
HRV is an interesting metric that indicates your resilience to stress. In general, the higher the HRV the better, as this Psychology TodayPsychology Today article explains. A low HRV means your body is working hard, which shouldn’t be a shocker if, say, you just ran a marathon. But if you have a low HRV and you haven’t been particularly active, it could be an indication of fatigue, dehydration, stress, or illness. Not all, but a growing number of high-end smartwatches and fitness trackers, including the Apple Watch, Fitbit Sense, and Oura Ring, offer HRV readings. The Fitbit Sense and Oura go a step further, also offering body temperature metrics, a feature not available on the Whoop at this time.
Respiratory rate is another useful metric to track, especially in light of COVID-19. A respiratory rate between 12 and 20 is considered average, but the Whoop will tell you where you fall within that range. I, for instance, typically average around 15.6 respirations per minute (RPM), according to the app. A sudden spike in your respiratory rate compared with your baseline can be an early indicator of COVID-19.
Shortly after the pandemic hit, Whoop added a feature to the journal section of the app that lets you toggle Yes if you’re experiencing COVID-19 symptoms. After adding the feature, Whoop says it quickly became apparent that users often experience an increased respiratory rate prior to reporting COVID-19 symptoms. The Whoop isn’t technically considered a medical device per the FDA’s regulations, but it can certainly help you keep a close eye on your overall wellness.
In the recovery section of the app, it shows individual values and graphs over the past week for your respiratory date, HRV, and RHR, along with your overall recovery score. A recovery score of 67 percent or above is considered Sufficient (meaning you’re ready for high-strain training), 66 to 34 percent is Adequate (meaning your body can adapt to but might be compromised by a high training load), and 33 percent or below is Low (indicating a rest day or revaluation of your lifestyle choices is in order). Sufficient scores are shown in green, Adequate in yellow, and Low in red.
I love to see a green recovery score, but there are certainly days I’ve fallen into the red. Between Christmas and New Year’s Eve, for instance, I logged three red recovery days.
Measuring Sleep Performance
After every night you wear the Whoop to bed, the app gives you a sleep performance score from zero to 100 percent, comparing the actual duration of your sleep to the amount you needed. Last night, for instance, I needed 8 hours and 41 minutes, but slept for 7 hours and 11 minutes, earning a sleep score of 83 percent, which Whoop says is “enough to get by.”
The app offers a wealth of in-depth sleep metrics, including the duration of your time in bed, your number of disturbances throughout the night, your sleep efficiency (the amount of shut eye you got vs. how much time you spent in bed), and latency (how long it took you to fall asleep). It also shows graphs of your sleep performance over the past week and your heart rate throughout the night.
The Whoop highlights interesting sleep trends, like whether you’ve been spending more time in bed than usual. It also reports on whether your sleep performance is trending up or down. As I’m writing this, the app says my seven-day average sleep performance score is 84 percent, which is higher than my prior 14-day average (72 percent). “Try to keep this trend going,” the app encourages.
If you have notifications enabled, the app will send you an alert in the evening with the amount of sleep you’ll need to perform at your peak the next day. In the alert, it will also recommend when to hit the hay, and when to wake up.
More Than Just Fitness Tracking
The Whoop Strap is a user-friendly health tracker that can aid anyone in pursuit of increased wellness. It monitors your cardiovascular load during workouts and throughout the day, the duration and quality of your sleep at night, and how well your body recovered from training and other stressors, based on your resting heart rate, heart rate variability, respiratory rate, and more. Its well-designed companion app makes it easy to understand your metrics, illuminates trends, and offers personalized daily training and sleep guidance to help you perform at your peak.
It’s among a growing class of wearables that go beyond fitness and workout tracking to help you monitor and improve your overall health, a category that devices like the Fitbit Sense and Oura Ring also fall into. Ultimately, all three are sold options, depending on your aesthetic preferences and desired features. The Whoop stands out for its excellent sleep and fitness coaching and monthly performance reports, but it doesn’t track your body temperature like the other two. The Sense features a gorgeous color touch screen, ample stress-management features, and useful smartwatch capabilities like mobile payments and Spotify support, but suffered from connectivity issues in testing. The Oura offers the most stylish design of the bunch, but its activity and workout features are pretty basic. The Amazon Halo also falls into this category; I’m testing it now, so look for my full review soon.
With a subscription pricing model, the Whoop Strap is an ongoing investment, but it might be the right one for you. Personalized monthly performance reports help justify the cost, and it promises to become even more useful over time through regular app updates with customer-requested features. As it stands, it’s already worth recommending.
