OMG, My Whoop 5.0 Flagged ‘Accelerated’ Aging

While the world of fitness trackers may have started out with watches, it soon moved on to other forms: Smart rings like Oura, and now arm bands have joined the chat. One of the most well-known of the latter is Whoop, a wearable that eschews the screen—and the distractions that come with it—in favor of a simple design made to stay on 24/7.

I was already trying out the Whoop 4.0 when news of their latest release hit. The Whoop 5.0 (free, but requires an annual membership ranging from $199 to $359, whoop.com) launched in May, promising better battery life, a sleeker design, and new longevity-focused data points (who doesn’t want to biohack their aging?!). Curious whether these new features warranted an upgrade, I swapped my 4.0 for the Whoop 5.0 for over a month to find out.

How I tested

I started wearing the Whoop 4.0 in the beginning of April—smack-dab in the middle of a half-marathon-training cycle. By the time the 5.0 hit shelves, the Whoop universe already had about six weeks of my data already logged, meaning it “knew” a lot about me (including baseline health metrics like resting heart rate and breathing rate). After I switched to the new 5.0, I wore it for five weeks. I followed the 24/7 model for wear, keeping it on all day (showering included) and all night, taking it off only for a wedding and for a couple days on a trip after its battery died.

Wearing the Whoop 5.0

The first thing I noticed upon unboxing the 5.0 was that the new design does look a little more refined: It has a lower profile, meaning slightly less likely to snag. I also tried it with the SuperKnit Luxe Band (included with Life, the highest membership tier), and the smart silver clasp gave it a slightly more sophisticated look than my 4.0’s black one.

I wore my Whoop 5.0 a few inches up from my wristbone, on the same side as my trusty Garmin Forerunner 265. Technically, Whoop recommends placing it one finger-width above your wristbone, but also clarifies that wearing it higher is “perfectly fine” as long as it’s snug and comfortable. That was good news, because as a runner, I kind of need the watch face during workouts to track time, pace, and distance, and my other wrist was a no-go due to a bunch of permanent bracelets soldered on there.

While the Whoop 5.0 is supposed to be sleeker, it’s still not exactly subtle. The 5.0 is smaller, but on my small wrist, it’s still a relatively bulky piece of hardware that doesn’t really disappear from view, regardless of being sans screen.

Getting started with the Whoop 5.0

Initially firing up the Whoop took more time than I’d like to admit. The Whoop band has a hooked piece of metal that attaches to the clasp, which then folds over and clicks on to secure. Sounds simple, right? Should be—but I’m embarrassed to say that I had to call my partner in for backup. (In my defense, he couldn’t immediately get it on, either.)

Because the device is screenless, the Whoop app is your gateway to all its bells and whistles, so it’s a vital part of the experience. (And a costly one: Whoop requires a membership, and you need the top-tier Whoop Life to get all the new features, which will set you back $359 a year.) I had some trouble pairing my device with its app for the first time—and repairing, since my Whoop randomly lost connection with my Android phone a few times during my testing period. Because there’s no screen on the Whoop, its lights are your guide and tapping is the way you “talk” to it. You tap the top until the green light changes to blue, which indicates it’s in pairing mode. And if the blue light doesn’t come on? Then you find yourself continuing to tap frantically like a fiend, until you finally give your fingers a long enough break to google some troubleshooting. (Force-quitting the app, forgetting my Bluetooth connection, and restarting my phone worked for me.)

Battery life for the Whoop 5.0

Simply put: amazing. While I used to eke out about three to four days of charge on the Whoop 4.0 (similar to what I’d get with my Garmin watch), the 5.0 came through with a huge upgrade. Now, I had my battery last for a whopping 13 days.

Another cool thing on the Whoop front is, you don’t have to take off your device to charge it. Whoops juice up with a tiny square battery pack. You charge that with a USB cable, and then simply pop it on top of your Whoop to transfer. That means truly continuous data recording, since you never have to remove it.

One callout though, for folks already in the Whoop world. The 5.0 is not compatible with the 4.0’s battery pack—and they look pretty darn similar, so it’s easy to mix them up (something I found out firsthand when I was traveling for my half-marathon and realized I grabbed the 4.0’s charger. Cue dead Whoop.)

What the Whoop measures

The home screen of your app is dedicated to three metrics key to the Whoop experience, and clicking through each yields a treasure trove of further info:

• Sleep: Measured overall with a “sleep performance” score on a scale up to 100%, this metric takes into account actual hours slept versus hours needed (a hard activity earlier that day would increase sleep need, for instance); sleep consistency (how the timing measures up to your usual); sleep efficiency (the percentage of time in bed you’re actually sleeping); and sleep stress.
• Recovery: You get an overall percentage on a scale of up to 100%, which considers metrics like heart rate variability, resting heart rate, respiratory rate, and sleep performance. A low recovery means your body is still feeling strain (see below!), whether from a harder effort, poor sleep, or stress, so pushing it would not be recommended. On the flip side, a high recovery score means all those metrics are in a good place, so you can go hard.
• Strain: Measured on a scale of 0 to 21, Day Strain combines specific strain scores you get for activities and the cumulative overall strain put on your body from simply existing in your day to day. You’ll get cool intel like the amount of time you spend per day in moderate and intense heart rate zones, steps taken, and time spent doing strength activities.

Basically, all of the data the Whoop spits out will be related in some way to these metrics, whether independently or in some combination together.

Working out with the Whoop 5.0

Thankfully, you don’t need to worry about tapping your device to get your Whoop to track—an “activity” will automatically generate once you exhibit “sustained, significant cardiovascular exertion” for at least 15 minutes. (Alternatively, you can also manually start an activity on your app; simply select from dozens of options, including staples like weightlifting, running, swimming, or Pilates, to more…uncommon ones, like caddying, disc golf, public speaking, or baby-wearing.)

My Whoop was very accurate at detecting my majors: running, spinning, and weightlifting. Shortly after completing my workout, I’d get a notification from my app that my activity was ready to review. Then, I was able to click through to get details, including Strain score, steps taken, and a nifty chart of my heart rate during that activity—as well as a breakdown of how long I spent in each heart rate zone, and how that compares to my typical range. (What you won’t get from the Whoop: specific performance metrics for your workout, like pace or distance.)

One really cool shoutout for the Whoop: It handles weight lifting better than any wearable I’ve ever tried. Usually, fitness trackers underestimate the physical strain of strength training. That’s because generally, your average heart rate isn’t going to be as high as it is during a sustained cardio activity—but that doesn’t mean you’re taking it easy. Whoop works around with a feature called “calculate muscular load.” Basically, you can input your entire workout, including specific exercises, reps, sets, and weight used, into the app for your routine, and then it’ll readjust the score based on the actual specifics. When I did this for one of my workouts, I got a Strain score of 14.7—much higher than when I didn’t use this feature. (In those cases, my Strain score hovers around 5–7.)

Full disclosure: It is time-consuming to input all of this data into the app, but the good news is, you can save your workout on the app and just select it whenever you do it. So if you’re repeating workouts—which, let’s be clear, really is the key to seeing results—it’s a whole lot easier to reap the benefits of this feature.

Recovering with the Whoop 5.0

The Whoop doesn’t only care about what you’re doing in your workouts. Whoop weighs sleep very heavily, and it also considers out-of-workout strain too, which it measures with its Stress Monitor. By analyzing your heart rate and heart rate variability, Whoop can detect when your body is stressed, whether that’s due to physical exertion or non-activity stress (the physiological stress that pops up during the day, like when work is crazy or you’re white-knuckling a doctor’s visit). Whoop will give you a Total Day Stress Score—falling into Low (blue), Medium (green), or High (orange) buckets—and that will combine with your other data points to influence Recovery. From my experience: A night of short sleep followed by a hard workout and a non-stop workday will earn you an orange stress score—and a plummeted Recovery the next day.

I was in the final weeks of training for a half-marathon when I started testing Whoop 5.0, and one of the most helpful parts of the app was the daily, seven-day graph you’d get on your home screen showing Strain versus Recovery. Because my workouts generally followed the same weekly schedule, I was able to see logical patterns (recovery dip after a hard mid-week workout, for instance) and some surprising ones—say, an unexpected recovery dip when my workouts were pretty chill. When that happened, it served as a red flag to pull back, since it suggested my body might have been fighting off a bug or something else stressing it.

Health and aging data with Whoop 5.0

Speaking of illness: Front and center on the app’s home screen is Health Monitor, five metrics (respiratory rate, blood oxygen, resting heart rate, heart rate variability, and skin temp) that are compared to your baseline levels and trigger a callout if any one of them is significantly off from your norm, potentially signaling something may be amiss. I found this super helpful because each was compared to my baseline, so when something was wonky, I knew it was off for my individual body, not some general average.

New to Whoop 5.0 is the ECG, an FDA-cleared health feature that checks your heart rhythm. Fire it up on your app, hold the device’s sensor between your thumb and index finger, and wait 30 seconds for your reading. I don’t have any specific heart concerns, so I didn’t use this feature often (and when I did, it often took a few tries to get it to finish), but it was kind of nice to see it spit out “normal sinus rhythm detected” with no signs of atrial fibrillation. (Whoop also processes your report as a PDF, showing a graph of your heart’s activity during the duration of the test. You can export it and share, which would be super helpful if you needed to show your health care provider.)

Another new feature—and probably the one I was most excited to try—was Healthspan, which uses Sleep, Strain, and Fitness metrics in its analysis. You get a Whoop Age, which compares how your body is aging to your chronological age. If your Whoop Age is younger than your actual age (mine was by six years and change, yay?), it suggests that you’re “exceeding recommendations for good long-term health.” Whoop Age looks at six months of data, so it’s more focused on long-term habits that span weeks or months and doesn’t really change much on the day to day.

What does change more: Pace of Aging (and, from personal experience, thank god it does.) Pace of Aging reflects your last 30 days of data, so it takes more recent habit changes into account than Whoop Age—which means you can see fluctuations by the week. And I sure did. The week of my half-marathon, I checked my Pace of Aging and was rather, um, horrified to see that it was 1.4 (meaning “accelerated” aging—my Whoop Age was increasing 1.4 times that of my chronological age.) The reason Whoop gave? It told me to keep an eye on my Strength Activity Time, which, to be fair, did drop over those past couple weeks—but only because I was tapering for my race! The following week, when I got back into my more normal exercise routine, it dropped to 1.0, or “stable” or “steady” aging, and now, it’s at 0.7, or, as Whoop helpfully describes it, as “reverse” aging.

My bottom-line experience with Whoop 5.0

After testing the Whoop 5.0 for five weeks, I’m convinced that it’s a recovery device rather than a workout device. It’s a tracker that seeks to help you reach your ultimate fitness potential not by pushing you to hit certain paces or strength PRs during your workouts, but by building holistic understanding of your body outside of them so you can learn when you need to take your foot off the gas—or when it’s time to floor it. By keeping your body in top form, you’re then able to give your all to those fitness pursuits.

For that reason, I’d consider it a great supplemental choice for someone who has big, objective fitness goals. For runners like me, you’re probably not going to get all you need from the Whoop alone—you’d be missing out on key intra-workout data, like time, distance, or pace, which you need in real-time. I wore my Garmin during the whole time I tested the Whoop; if I didn’t, I would have had a really tough time getting through my running workouts.

The overall recovery experience with the Whoop is hard to beat, though, and it’s definitely picked up on things that my Garmin didn’t, like days I needed to take it easy rather than push. It’d also be a great overall wellness tracker for folks who don’t need real-time workout data in front of them. In fact, it might have the edge over the Oura, in my opinion, since you can keep the Whoop on while lifting, which you can’t with the ring. And thanks to new features still in beta (such as Blood Pressure Insights, which provides estimated readings once a day, for Whoop Life users), it could be a helpful device for those who need to keep a closer eye on that.

Finally, because the Whoop is pricey—you have to pay for yearly membership—folks who are just dipping their toes into the fitness world may be better served by a more entry level option. It’s likely going to be a better choice for those who have the desire and the means to invest in higher-tech fitness accessories that go beyond shoes and sports bras.

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