It was only a few months ago that we reviewed the WHOOP 3.0 fitness band.  In true tech fashion, not long after WHOOP 3.0 became obsolete when WHOOP 4.0 was released.  Luckily, the WHOOP sales model involves a subscription to their service which includes a free upgrade to their latest hardware.

Alongside the new 4.0 fitness band, WHOOP also announced WHOOP Body, a new way to wear your WHOOP tracker for different occasions/scenarios or for when the wrist strap isn’t feasible.  WHOOP sent us their newest model along with a spare Superknit band for different styling and a compression shirt for times when the strap could not be worn. 

WHOOP 3.0 vs 4.0: Design differences

WHOOP 4.0 is a lot smaller than the previous version while at the same time it has the same five-day battery life.  Even with the smaller size WHOOP has packed in four times the number of photodiodes on the sensor and five LEDs that use green, red and infrared light for new metrics and improved accuracy in the data collection.

The smaller size makes the band a lot more comfortable to wear 24/7.  Normally I hate to wear my watch around the house, especially when sleeping, but the slightly smaller size made the WHOOP 4.0 a lot more comfortable and easier to get used to.  

The way the strap attaches to the sensor is now a simple slide making it easy to attach a different strap so you can style it however you want with a minimum of fuss.  It was handy and if I was going to continue to use the WHOOP 4.0 permanently, I would be buying assorted styles of bands.

Another improvement WHOOP made with the 4.0 version is the inclusion of a vibration motor to create vibration alerts and, in their words — take the Sleep Coach to the next level — with the inclusion of a vibrating alarm.  I’ve been getting up for the gym (now that I don’t have to make do with garage equipment) at 5:50am and to be woken up by a softly vibrating band on my wrist instead of any sounding alarm is a lot more pleasant — not only for me but for my wife also.  

It is strong enough to wake me from the deepest of sleeps and hasn’t missed a single beat.  WHOOP gives you the option of setting the alarm three ways — to wake at an exact time, when you’ve hit your sleep goal or when you’ve optimally recovered.  I assume this is for professional athletes who do not have to get workouts done before having to go to work.  Me, I can’t ever see a time where I wouldn’t set it for a specific time so I can get as much sleep as possible!

Another improvement is that the new battery pack is smaller but packs the same amount of stored power and is now waterproof.  There is no need to ever take your band off anymore — even if it is due for a charge while you are swimming or in the shower you are good to go.

New Features

So this must mean a heap of new features right?  Sort of.  There are a few but how many of them are actually useful everyday remains to be seen.  

The new LEDs allow WHOOP 4.0 to monitor blood oxygen levels (SpO2) with pulse oximetry, something a couple of the more advanced smartwatches can now do.  Obviously for the serious athlete this can help with their training regiment along with to determine how their lungs are functioning — I wonder if this could help to detect COVID function changes?  I assume so but let’s hope no one here ever needs that and if you do I hope you head to your closest hospital.

The new sensors also help to determine various heart rate measurements including the current heart rate, a resting heart rate, heart rate variability (I might try and wear it this week at basketball in the WHOOP Body compression shirt), and respiratory rate.  These are all shown in a single location in the WHOOP app which you can then share with your physician, trainer or friend (to brag I assume).

WHOOP 4.0 still does not have an inbuilt GPS so it you are going for a run you will need to carry your phone with you if you want to track your run. I’d say, if you’re a runner then WHOOP 4.0 may not be for you.


For me, the only training I do is weight training and when I’m wearing wrist supports (for chest day) or wrist straps for grip strength (back day) the WHOOP band cannot be worn as it interferes with this.  For this reason, WHOOP Body is a godsend for me.  I was able to remove the sensor from the strap and slide it into the sleeve of the compression shirt (the pocket that houses it has a Velcro opening so it won’t fall out) so that my vitals etc can still be measured the entire time while working out.

Other WHOOP Body products are also available including bras, boxer shorts, normal shorts, leggings and more.  All of them come with a simple pocket to house the sensor so that it can continue monitoring your vitals, out of sight.

WHOOP Body compression shirt that I tested was great quality. It certainly is a compression shirt and fits true to size — if you are normally a large in compression shirts, get a large. They wash easily and my wife tells me it was nearly dry as soon as she pulled it out of the washing machine after the spin cycle.

WHOOP also sent me a grey band with silver clasp to change up the look from the basic black.  It was super simple to slide the old one off the sensor and the new band on.  As I said above this is something I would be buying more of if I was going to be using WHOOP permanently — although the bands are not cheap.  If you buy a spare one with a clasp the cheapest available is currently $28 on sale ($55 normally) but if you don’t mind using the same clasp each time (and it’s not that much of an imposition to use the same clasp — it just requires a bit more time for the swap) then you can get the band only.  A band only can set you back as little as $17.

So how much is WHOOP 4.0?

WHOOP membership with WHOOP 4.0 included is cheapest as an 18month subscription for $432 — $24 per month but if you sign up to just 6 months it will cost you $44 per month.  Not cheap but if you are a serious athlete and want to get the most out of your training it may well be worth it — it’s less than a smoothie a week.

WHOOP has now included a new level of membership called WHOOP Pro which will cost you an extra $12 per month.  The Pro level gives you 20% off all items in their store with free shipping on every order, a free item every 3 months, including bands, batteries, WHOOP Body, and more.

So would I still recommend it?

WHOOP 4.0 is great but it still does not have a screen. A simple clock with a heart rate display is all I ask — like the older, simple Fitbits. Without it I have to wear the WHOOP 4.0 on one wrist and my watch on the other. Of course, you could just wear a different piece of WHOOP Body clothing every day to get your measurements but that makes the whole exercise even more expensive.

The advantage of WHOOP 4.0 is that even though you have an ongoing subscription (more on that in a bit), it seems that they will update your hardware each and every time a new piece comes out. For example, if WHOOP 5.0 arrives sometime next year you can be fairly sure they will give it to their subscribers, otherwise all you’d have to do is unsubscribe and resub to get the hardware. May as well keep the subs running — from a company point of view so I can’t see them messing with this.

Now, the subscription is not cheap, but it is comparable with similar services. These days most fitness tracking services only offer the bare essentials on their free tier. You have to pay a similar sub price to WHOOP to get more detailed information. WHOOP does take those details and information further than other apps I have used with their coaches and their ability to use your training and stress levels to tailor your performance/workout on that day — it takes all of your guesswork out of it for you. Other sub models mostly just provide the information leaving you to your own devices to analyse it.

WHOOP 4.0 is for those serious about their workouts and their exercise. Simple as that. It is an extra device you will need on top of a watch etc (unless you don’t wear a watch). If the subscription was a bit cheaper it would be easy to recommend to all people who love to exercise (and those who don’t but still do it) — it is $24 per month in its cheapest purchase (locked in for 18 months). In the end it depends on what you need and how much you need it. For the serious athlete I can say that WHOOP 4.0 will help you get the best out of yourself.

For the cost of one gourmet burger and chips per month (I’m sure that’s a currency somewhere and if not, it should be) you can get WHOOP 4.0 and its subscription for 18 months. WHOOP body, from what I tested, were excellent quality clothing and if you are going down the WHOOP path I can highly recommend them.

For more information, head on over to the WHOOP website and sign up.