Whoop Strap 4.0 Review

by -132 views


While it remains the about inventive approach to athletic performance and recovery, Whoop’due south new health tracking tools make information technology an addictive and reliable dashboard for your overall wellness.


  • The Strain/Recovery focus still feels ahead of the pack
  • Useful new daily health monitoring tools
  • New waterproof battery pack
  • Versatile wearing with Whoop Trunk accessories


  • Conditioning tracking tin can feel secondary at times
  • Subscription model only
  • No screen (could besides exist a pro) and no GPS

Key Features

  • 33% smaller pattern
    New build includes 5 LED sensors, merely cut physical footprint by a third

  • Waterproof battery back
    External battery pack now IP68 waterproof every bit well as strap

  • New wellness monitoring tools
    Skin temperature and bloody oxygen readings join HRV, Hour, respiratory rate, sleep tracking and much more


Every bit the pandemic raged in 2022, 1 fettle clothing showed value in indicating when people had Covid. Studies showed that, prior to symptoms emerging, the Whoop Strap’s detection of a heightened respiratory rate was telling.

Once symptoms did appear, the mode Whoop detects how the body recovers from the strain was telling another story. Many reported the center rate variability (HRV) based Recovery data was as low equally 1%. Put plainly, it quantified the ass-kick Covid was giving their bodies.

Whoop Strap 4.0 on the wrist

I’ve used every generation of the Whoop Strap. It’s far from your average fitness tracker. The premise is to find the perfect residue between how hard you railroad train and how prepared your body is to handle it. If your mail-sleep recovery score is depression (either through a poor/limited slumber, disease, a few beers, or a particularly intense workout the previous solar day) then you shouldn’t go as difficult. If your recovery score gives you a literal green light, yous can push yourself with a much lower run a risk of injury. It was designed for elite level athletes – like NBA stars who have to peak at the right time – only it has uses for every twenty-four hour period recreational fettle enthusiasts besides.

The more contempo data revealed Whoop was potentially merely every bit effective as an overall health monitor, across its athletic prowess. Information technology’s something the well-backed start-upwardly has doubled down on with the new, redesigned Whoop Strap 4.0. It adds blood oxygen readings, pulse oximeter capabilities and a skin temperature sensor. They’re all enabled by the new LED array inside the device.

Toll and subscriptions

A couple of years back Whoop pivoted from being an expensive $500 sensor to a subscription model. You get the Whoop Strap 4.0 complimentary but you pay a subscription fee to access the app and back up and community features over a -half dozen, 12-, or 18-months period. A six-month membership is £180 (£30 a month), a one-year sub is £288 (£24 a month) and an 18-month membership is £224 (£xviii a month). If you owned a Whoop Strap 3.0, you get a free upgrade to 4.0.

You might like…

Design and build

  • At that place’s no display hither
  • The strap is replaceable
  • Battery pack helps charging on the go

This device has never had a display and that doesn’t change here. Equally ever the band stretches over the top of the wrist worn sensor itself and clips into place.

Yet, Whoop Strap does become its first meaning redesign since the first generation of the product. Information technology’southward 33% smaller overall and noticeably and so. Thankfully it’due south still compatible with existing replacement bands, as I have loads of them. At that place’s too a new Fast Link system that makes changing new ones easier.

Whoop Strap 4.0 in two colour options
Whoop 4.0 (right) vs Whoop 3.0

It likewise has a new v LED array using green, ruddy and infrared light to support those additional health monitoring metrics while promising to improve data accuracy. The new generation has as well added haptic feedback, which helps the Sleep Charabanc wake yous at the optimum signal in your recovery, or when information technology hits green.

Whoop Strap 4.0 with charger
Whoop 4.0 (lesser) vs Whoop iii.0 (elevation)

The external battery, which slides over the pinnacle of the device and is however worn while the device is charging on your wrist, also gets a new design. Information technology’s now waterproof (IP68), meaning you can besides wear information technology in the shower while the device is recharging. The Whoop is most effective when you never take it off, so this removes another scenario when y’all may have to remove it. The device and battery pack are waterproof to 10m.

Every external Whoop battery I’ve owned has failed and stopped charging the device much sooner than I’d expect (within a twelvemonth) meaning that you lot really demand two on hand to maintain continuity. Whoop tells me that this may have been down to damage (wet or otherwise) acquired to the exposed copper contacts that were required to connect to the device itself.

At present these are gone (you can run into the difference beneath) as part of the waterproofing of the battery, and the battery charges via a wireless technology that senses when there’s a connectedness detected between battery and device. Fourth dimension will tell whether the technical revamp has resolved the longevity issues I’ve experienced previously.

Whoop Strap 4.0 charger

Tracking and Recovery

  • Don’t expect this to work in the like way to an Apple Sentry
  • Multiple areas tracked

As mentioned to a higher place, Whoop does things a footling differently to your average fitness tracker. The Day Strain score is measured on how much your centre charge per unit is taxed during exercise. Activity is automatically tracked, but you can start/end/add activities manually for more than precise information on individual workouts.

The key metrics tracked are equally followed:

  • Day Strain: How difficult yous’ve worked your heart throughout the day (from 0-21). As this is solely dependent on raising your HR, you’re non getting much credit for regular walking, unfortunately.
  • Recovery: How well your body has recovered from exertion. It’due south based on how well and how long you lot slept for, and your middle rate variability reading (0-100% and reddish, yellow, green indicators)
  • HRV:The variability of time between heart beats. The higher the score the ameliorate, and a skilful score for me (practiced sleep, no booze, proper practice the previous day) was generally in the 50s
  • Calories: Whoop has never been considered a calorie-counting device, only it still does so, breaking down an overall metric for tracked activities and the twenty-four hours itself.
  • Sleep: Automated sleep tracking with stages measures time in bed, time awake, light, deep, REM sleep also every bit the disturbances throughout the dark. You’ll get a Sleep Performance score (%) depending on how much sleep you got and how much Whoop calculated you needed for recovery.
  • Health monitor: Here lies info on your respiratory rate, resting heartrate, blood oxygen level and pare temp compared to a baseline. If anything dips in the incorrect direction, you’ll be notified. If your respiratory rate and blood oxygen level drops, for example, this could be an indicator that you lot’ve been struck down with Covid. I found this was worth checking in on once a day. You tin can also save a 30-day wellness report as a PDF or print it off to share with a medico, trainer or whoever…

While Whoop automatically picks up elevated heart rates and adds information technology to your solar day strain, yous’ll want to log your private workouts for more than granular information. You tin can do this earlier setting off on a run, for example, for live tracking, real-time strain accumulation and connected GPS via the app for distance stats later on. The live tracking also has the do good of a notification when you’ve hit your optimal strain for the day. Handy to finish you lot pushing likewise hard.

You can too add the activity after the fact by choosing the discipline and logging the time you lot started and stopped. So, if you come up out of a yoga class at viii:05, you can log the concluding hour or so of activeness.

Whoop Strap app running workout

Once processed you’ll see a strain score for the activity (which is added to your daily tally) along with a helpful graph representing the peaks and troughs of your Hr along with the boilerplate and max HR, calories burned and insight such as “yous spent 24 minutes at 60-seventy% of your max 60 minutes. This is 4 minutes more than than you lot typically spend in this Hr zone during yoga”. At that place’south also user inputted performance levels and perceived exertion for your own records.

In terms of accuracy, a wrist worn Whoop performed admirably in tracking heart rate data aslope the breast-worn ECG-based Polar H10, still seen as the golden standard, by and large staying within a couple of BPM either manner. You lot won’t become the same detail on your conditioning stats as y’all would from a high-end Garmin watch, which tin can offering power and Vo2 Max, for case. One criticism that can be levelled at Whoop is that the activity tracking itself can feel a little secondary to the overall Strain vs Recovery concept. Yous won’t even get mile splits for your runs, for case.

Whoop Strap 4.0 with grey strap

In that location’s a large array of activeness types and the full waterproofing ways it’s platonic for swimming too. At that place are multiple places where you lot tin can wear your Whoop (at that place’s a bunch of accessories available, including a ‘performance thong’!) and one time you tell the app where, it has a better shot at machine classifying the activities.

I tried the boxer shorts (below) which enables you to slide the sensor into a piddling pocket in the waistband after removing the strap. Equally the sensor needs to stay in contact with the pare, the waistband is quite tight (my pandemic bod’ still) so they aren’t the nearly comfy boxers to article of clothing. I likewise found I burned roughly 120 fewer calories for the same yoga workout when I was wearing the boxers.

Whoop Strap 4.0 app
1 hr yoga course wrist worn (left) and waistband (right)
Whoop Strap 4.0 being worn

Recovery measures the trunk’s post-slumber render to its baseline state following a stressor like exercise, stress, poor slumber, alcohol consumption, et al. It factors in your resting center charge per unit, heart charge per unit variability, respiratory charge per unit, and sleep operation to requite you a score between 1-100%.

Blood-red: 0-33%:
Consider a low training load

Yellow: 34-66%: Proceed with caution. This might not exist the day to push

Dark-green: 67:100%:
Y’all’re primed to let rip with a high strain day. The app will tell yous how hard you can go.

I’ve continually found this to be the near compelling element of the Whoop proffer. More ofttimes than not, I feel as my recovery score suggests. A few beers and a rough night’s slumber, then I’one thousand every bit the 22% recovered man Whoop projects. An early night following a 24-hour interval where I exercised a good for you amount and ate well? Sentinel my 82% self dominion the day and button towards higher day strain.

You lot can gamify this if y’all wish. Shoot for a college recovery score so you lot can go harder in exercise, at the gym, or on your run (or just to feel ameliorate). You can listen to the Sleep Charabanc which tells you when you lot need to go to bed to optimise your recovery, or not have a second glass of wine considering yous know it’ll limit your recovery.

Whoop Strap 4.0 recovery app

It helps with making informed, salubrious decisions. The recovery score is in tune with my body and my mindset. It besides helps with continuity and being able to perform the next day. If you stay within your optimal strain range, the chances are you’ll be able to recover and go once more the adjacent day – especially if you listen to the sleep coach, which tells you how much slumber you need to get dorsum in the greenish zone. This is designed more for elite athletes, but recreational users tin find it useful too, peculiarly if they’re trying to adhere to a routine.

There’ll always be those “hustle culture” bores who tell you lot the days you lot don’t feel like grooming are the ones where you’ll experience the most benefit. This device quantifiably says “bollocks” to that. And I, for i, appreciate it.

During this review I lost the external battery pack and the device ran out of juice. I soon came to miss it, like yous’d miss the dashboard instruments as a car. I go through stages of using Whoop and not, but when I’chiliad all in, it feels indispensable. That helps to explain the visitor’due south switch to a subscription model. Information technology tin feel “must have” when you’re in that groove.

Whoop App

  • Vital add-on due to the lack of display on the device
  • Handy summary of your stats
  • Option of delving deeper into your stats

As there’southward no screen – a godsend for me and one of the key reasons that I continue to use Whoop out of option, non for work – the merely touch on interaction you might need with the device itself is a double tap to show an indication of remaining bombardment life. So, it’southward all about the app. Whoop 4.0 builds upon a consistently practiced app experience with the new health monitoring technology, which you can run across below.

Whoop app health monitor

The overview section withal provides a summation of your recovery, electric current strain for that solar day, your overnight HRV and calories burned. A snapshot of your sleep time and any activities yous’ve logged are below. Further down the screen are the health monitor and strap status (indicating battery life and last time data was synced). You lot can hit the calendar view to encounter a snapshot of the days where you exceeded a 10.0 Day Strain too.

Whoop app overview

In that location are also tabs where you accept a deeper dive into your Strain, Recovery, Sleep stats. The clipboard screen enables you lot to delve into the sleep charabanc, health monitor and performance assessments. You tin can take and selfies if you wish, with your stats overlaid, and join/create teams to mensurate your progress confronting.

Ane thing I’ve noticed with the afterwards generations of Whoop is that the data syncs much quicker now. When using the first generation or 2, you lot’d be refreshing the app trying to become it to catch up, just it’s practically instant these days. At that place’s also plenty of helpful notifications nigh battery power and intelligent nudges from the Slumber Motorbus informing you to go to bed if you desire to hit optimum recovery for tomorrow’s game or workouts.

Battery life

  • A single charge last for a four-5 days
  • External battery helps charging
  • You never really have to take the Whoop off

In the early days of Whoop, I was having to charge my Whoop strap every 36 hours or and then and it was a real hurting. Now you’ll go a reliable 4-v days of solid use out of it, taking away some of the worry. Whoop wouldn’t say the actual size of the internal bombardment, just the external pack, which can bring it from 0-100%, is 638mAh.

Because the device doesn’t have a brilliant screen draining that bombardment or GPS during workouts, you could perhaps expect a bit more. These sensors are working overtime though.

Recharging via the battery pack takes simply under two hours, so you don’t have to deal with the brunt of wearing the battery besides long. Best of all though, y’all never have to take Whoop off anymore every bit the external battery pack, charged independently via USB-C is waterproof. From that perspective information technology still has a leg up on pretty much every wellness/fitness-tracking smartwatch or wearable out there. After all, how tin y’all get the truly holistic picture if you have to take it off to charge?

Whoop Strap 4.0 with charger

Should you buy information technology?

If you’re seeking a holistic approach to health and fitness tracking: Whoop tin exist an incredibly helpful and informative tool that motivates y’all to make smart choices and perform to your potential.

If yous prefer to measure performance by traditional metrics like miles and calories burned:
The conditioning information can experience secondary at times, beyond the strain score and 60 minutes readings. At the end of the twenty-four hour period, this still serves high-level athletes best and the subscription-based model won’t exist for everyone, either.

Concluding Thoughts

Whoop 4.0’s smaller pattern, new sensors and new battery tech make it an extremely worthwhile update, particularly with the new health monitoring capabilities. As useful and pertinent every bit the Strain vs Recovery proposition remains, information technology still feels most useful for serious athletes. Nevertheless, if you buy in, nosotros think yous’ll probably stay in in.

How nosotros test

We thoroughly test every smartwatch we review. Nosotros utilise manufacture standard testing to compare features properly and we use the watch as our main device over the review period. We’ll always tell you what nosotros find and we never, ever, take money to review a product.

Worn equally our main wearabpe during the testing menstruum

Eye rate data compared against dedicated heart rate devices

Side-past-side comparison with our best scoring smartwatches

Yous might similar…


Tin you buy the Whoop Strap four.0 outright?

No, the Whoop Strap 4.0 is merely bachelor via a subscription model.

Does the Whoop Strap 4.0 have an warning?

Yes, you can at present set an warning time via the Whoop app and have the Whoop Strap 4.0 vibrate on your wrist.

Does the Whoop Strap 4.0 work with Android and iOS?

Yeah, the Whoop Strap is compatible with iPhones and Android phones.

Trusted Reviews test information

Discrepancy of highest BPM vs a breast-strap monitor

Fourth dimension from 0-fifty% charge

Fourth dimension from 0-100% accuse

Whoop Strap 4.0


52 Min

110 min

Full specs


IP rating



Size (Dimensions)


Release Date

First Reviewed Date

Model Number


Whoop Strap 4.0




638 mAh

20.five ten 35.87 x 10.4 MM

eleven.3 Yard




Dozens of bands bachelor

Source: https://www.trustedreviews.com/reviews/whoop-strap-4-0

Posted by: Sadiyev.com