Whoop 4.0 Review: Smaller, Smarter, and Still Unnecessary

The most hardcore athletes have always been marketed to be the most hardcore. It is designed to maximize training and has been seen on the wrists of athletes in the NBA and other pro sports leagues. I don't want to wear something on my wrist that doesn't tell me the time of day. It is true, but I should be called old-fashioned.

I figured it was time to try out the fourth generation of the wristband, which is 33% smaller than its predecessor and has more sensors, so I did. It gets a lot of things right.

A device that is laser focused on your recovery and strain levels.

If you sign up for 18 months, you'll pay $18/month.

It does a good job of monitoring your heart rate and has the best charging solution of any Wearable I have tested.

It doesn't have a display, it doesn't track anything other than sleep and recovery, and it is often inaccurate with those metrics.

No screen, just a band.

The world of Wearables has always been unique. It isn't something you can just buy. It can be as cheap as $18 a month if you buy in an 18-month chunk, but the company will send you the band for free. If you have been using the program for a long time, they will send you a new band for free, and the old one will cost more.

The sleeker design of the Whoop 4.0 is what makes it different from previous versions. When it is on your wrist, it is less prominent and more comfortable. It claims to be the first to use a new type of battery from Sila, which has a silicone anode that has more energy density. Even though it is smaller, the 4.0 still promises five days of battery life.

The way the Whoops replenishes is very slick. It has a small battery pack that you just slip onto the Whoop and you don't have to take it off and there are no gaps in your data. If you want to shower or swim with it, it's waterproof so you can. It is a very clever system.

There is now a line of clothing called Whoop Body, which is similar to the watch worn on your wrist. You can wear the sensor elsewhere on your body with this collection of shirts, shorts, bras, underwear, and bands. I didn't have the chance to test these, but I found it to be very comfortable, even though it stayed on my wrist for a month. The woven band is soft to the touch, but it takes a little while to dry, which caused some damp cuffs.

What are the tracks?

The band doesn't have a way to count your steps or flights of stairs. No one knows or cares about trivial frivolities. It pays a lot of attention to your heart. The 4.0 band now has five lights, up from two in the previous generation, and it has four photodiodes, up from one.

The Whoop platform only cares about two things: your strain level and your recovery level, and that's effectively part of your recovery. Your strain score is how hard your heart had to work. The band keeps track of your pulse when you do a workout, manual labor, or anything that gets your heart pumping. You will see a strain score for that activity after. You get a strain score for your entire day, which is on a scale from zero to 21, for some reason. When you wake up the app will give you a recommended amount of strain to aim for based on how you have recovered from your last bout of strain.

Recovery examines how much rest you have gotten after training. The main way to recover is to sleep. Each evening, you get a notification that says how much sleep you need to get yourself a recovery score of 100. The strain score is 0-21 and the recovery is 0-100, but I don't know why. In my experience, the band estimates when you fall asleep and wake up with very solid accuracy. It monitors your pulse, heart rate variability, respiration rate, and blood oxygen levels while you sleep. When you wake up, it gives you a sleep score and tells you how you have recovered.

Not accurate.

I was excited to try it out for myself because I have friends and colleagues who get obsessed with their scores. The results left me underwhelmed. I found the strain metric to be inconsistent. When I woke up, it gave me a score in the low 4s, but it did not spike my heart rate. It seemed to work well for cardio, and my strain score would scale up as expected on longer/harder runs, but I don't know what to do with strength training. A lot of people do bodyweight exercises and lifting weights, but they don't register on the Whoop because they don't cause your heart rate to spike. This could leave you with exhausted, twitching muscles but still a low strain score.

I checked the heart rate against a chest strap heart rate monitor and against other Wearables, and generally the heart rate was accurate, though there were instances where my reading would just drop out unexpectedly, as you can see from these random sharp valleys in this run I recorded.

I would put it on par with other current generation Wearables, but not above.

I had issues with the way the Whoop scores sleep and recovery. The band gave me a 75 and I felt like I was at about 75%. It could happen in either direction. It told me that I was well into the 80s in my recovery and that I was going to have a hard day. I was exhausted and felt like a husk. It rated my recovery as way down in the 50s, but I was ready to work on it and felt great. I think the problem may be that Whoop weighs your heart rate variability more than it does the actual duration or quality of your sleep. HRV is an important metric, but people who are in good shape tend to have higher rates of HRV, which is a good thing.

It was a shame vs. Garmin.

It is worth noting that the first to really laser focus on recovery is the one that is called Whoop. I found the Body Battery metric from Garmin to be slightly more accurate than the recovery score I had, because it was the same thing. If you want it, this number is right there for you.

The crux of the issue is brought to us by that. I wore a watch called the Enduro for more than a month while I wore the Whoop 4.0. The Enduro can do so much more than the Whoop can. How about steps and altimeter? Check. Track all kinds of indoor and outdoor sports. Yes. Do it all with the ability to see the weather and phone notifications? Yessir. Is there no contactless payments? Yes. I don't have to pull out my phone to find out what's happening. If I want to see my heart rate in real time, I can just look at my wrist. I can set an alarm on my wrist. It is all right for me to know the number of calories I have burned, the flipping time and date, or my Body Battery level. Is it several weeks of battery life? That too. The Enduro is not a cheap watch, costing around $800, but it is one of the cheaper multi-sport watches that will last you a long time. The cost is likely to become comparable in a couple years.

The most important part is that the Garmin can replace the Whoop, but not the other way around. I don't like wearing two watch-sized Wearables for any activity that I do, and I don't like having the Garmin on for basically any activity that I did. It looks like I am a nerd.

Is it worth buying?

The Whoop is limited and not bad. It is great to see it evolve and do things that the 3.0 couldn't. It can alert you if your blood oxygen suddenly drops below safe levels, which could be a sign of a real health problem. When I got my Moderna booster shot, I woke up the next day to an alert that said my HRV had dropped, my skin temperature had risen above my average, and my recovery was very low. I felt bad for a day. You can use the vibrating motor in the 4.0 to set a silent alarm. You can set it to a specific time, a sleep goal, or when the Whoop senses that you are in the green. I don't recommend that last one, as it woke me up an hour earlier than I had hoped, and I was still exhausted.

Goals in and of themselves are good. The idea of calculating strain and recovery so you know how hard it is to push on any given day makes sense. The only thing that it does, and that is really the only thing that matters, is that it needs to be effectively perfect. There are a lot of sports watches out there who do a good job at addressing the strain/recovery equation, but then also do a lot more. A good multi-sport watch makes sense for most people.