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Evening Standard
Evening Standard
Lifestyle
Ellie Davis

WHOOP 4.0 review: the fitness tracker brand launches new AI features

Here’s something that will annoy 99 per cent of parents with young children, those with early office starts and anyone who doesn’t roll out of bed until minutes before the start of the working day: I was getting around nine hours of sleep per night and still waking up tired.

I didn’t understand. Was I oversleeping? Very possibly, but it didn’t feel like it. I decided I needed to know more about the situation and after hearing nothing but rave reviews about the WHOOP, I decided to take the plunge on the fitness tracker.

You may not have heard of WHOOP directly but I’m betting you’ll have spotted the elasticated strap on pro athletes like LeBron James, Rory McIlroy and Michael Phelps. The human performance brand has become hugely popular in the world of wearables for its personalisable approach to performance monitoring and enhancement.

It constantly measures your heart rate and stress levels, with further metrics for strain and recovery before providing recommendations and feedback to make it easier than ever to stay in tune with what your body needs. After conducting studies, it was found that the WHOOP can positively change behaviour, increase sleep, and improve physiological biomarkers.

(Getty Images)

Now in the fourth iteration, the label has advanced its accompanying features by introducing AI into the equation. Dubbed WHOOP Coach, it was created in line with GPT-4, OpenAI’s most advanced generative system in order to provide users with on-demand coaching.

But is it worth the hype? We strapped up - and strapped in - for the last month to find out.

WHOOP 4.0 key specs

  • Battery life: Officially five days but I found it lasted around a week
  • Compatible devices: Apple and Android
  • Charge-up time: around two hours
  • Colour: different straps available; block colours (black, white etc.) as well as patterns and rainbow designs
  • Measures: sleep, strain, recovery, log habits, stress, heart rate, blood oxygen and skin temperature
  • IP68 dustproof and water-resistant at depths up to 10 meters

First impressions

This is not your average fitness tracker. Unlike the ubiquitous fitness tracker-smartwatch twofers that dominate the market, there is no time-telling interface. Instead, there’s simply a strap with a sensor attachment. It’s not exactly subtle but you get used to it quickly and it has a more slimline appearance than the previous 3.0 model.

The black colourway that comes as standard is slick, but there are different band attachments to shop to make the gadget more suited to your style.

(WHOOP)

Set-up

After downloading the companion app, the trickiest element of the setup was working out how to take off the gadget but luckily removal is rarely necessary as the sensor is water-resistant so can be worn when showering, swimming in both pools and saltwater, bathing and the like (but crucially, not scuba diving).

The WHOOP comes complete with a portable battery pack. It’s about the size of an Oreo and charges via a USB-C cable. The pack slides on top of the sensor, meaning that it powers up the device as you’re on the move so you never miss out on crucial data collecting. The on-the-go charging function sets it apart from other fitness watches that require removal and plugging in. My one tip? Don’t lose it.

Place the sensor on the wrist, strapping it around one inch or the width of your finger between it and the start of your hand. The strap should touch the skin underneath.

As far as the app is concerned, fill in the basics (D.O.B, height, weight etc.) and the coach element. The latter details your goals, whether that is to be healthier, improve fitness or optimise your performance. I went for the first option (as do 24 per cent of members) and it guides you to balance the three elements of sleep, strain and recovery.

(WHOOP)

Features

Before diving into specific features, it’s important to stress how hi-tech this seemingly unsuspecting band really is. Not only was it somehow still able to collect data overnight when I forgot to charge it up but also when I had accidentally switched Bluetooth off my phone - and that’s just the tip of the iceberg.

Improvement from WHOOP 3.0

The souped-up WHOOP 4.0 has five LED sensors measuring more elements of your health than the previous model, including skin temperature and blood oxygen levels and displays resting heart rate, heart rate variability, and respiratory rate in easy-read graphs. All the information can then be downloaded as a PDF to show to a doctor, physio or PT.

Sleep Coach

This was the element that I was most eager to discover. For data nerds like myself, the WHOOP’s capabilities were nothing short of fascinating.

What became clear in the first few weeks was that while the time I spent in bed (it knows!) was normal, the amount of sleep - and more importantly restorative sleep (REM) - that I was getting was low. Unbeknownst to me, I spent most of the night awake or in light sleep modes, none of that deep, dreamy stuff. No wonder I always felt shattered!

Sleep is essential for not only recovery but for the immune system and performance, and the bar charts give a greater understanding of what your body needs, suggesting bedtimes to help you achieve your goals.

(WHOOP)

Additional handy features include an alarm that can wake you up at the time of your choosing - so far, so normal - but also when you’ve hit optimum levels of shuteye or when you’ve sufficiently recovered from strain.

Strain

Strain relates not just to working out but anytime that you’re stressed - be it at work or burning the dinner. It categorises these strains into zones based on your heart rate, while allowing you to set targets if you’re say, looking to be more active. There’s even a Strength Trainer feature where you detail weights used, reps and sets so you can deep dive into the stress on your muscles and joints.

While I am by no means an athlete, I do around three or so gym classes a week and I am prone to burning the candle at both ends with a work hard, play hard mantra. The effect of this is detailed as plain as day (in red) on the app, nudging me to devote more time to the recovery stage. It’s not just a simple case of nagging you to work out or hit 10,000 steps. WHOOP sees your body needs time for relaxation and guides you accordingly.

Stress Score

Perhaps one of the most interesting elements of the app is the stress graph. I consider myself to be a fairly laissez-faire person so seeing my stress spike during certain moments in the day was incredibly interesting - although what I was doing at 11.45am on a WFH day that made it suddenly shoot up I found it hard to pinpoint.

Heart rate variability

This is some hi-tech stuff. Using this feature alongside resting heart rate, respiratory rate, SpO2, sleep performance and skin temperature, the WHOOP revealed that I was likely ill - and it was spot on. My HRV level was lower than traditionally, meaning my recovery was lower and I needed more sleep to make up for it.

AI Update

WHOOP has entered the AI space with this new functionality from OpenAI. The added feature of the GPT-4 gives users the ability to ask specific coaching questions to the app’s chat box interface and get individual responses. This is done through the brand’s proprietary WHOOP algorithms and personalised with your data - the first of its kind.

You can get bespoke training plans or suggestions for a big upcoming race, get insights into your health if you’re constantly sick, and decode some of the more technical aspects of the fitness tracker. You can also ask to compare your data with people your age or general troubleshooting about WHOOP functionality. While this is cool to play with, it’s one of the less impressive features compared to everything else the wristband offers.

Verdict

There’s always a fear of knowing too much about yourself. I wondered if I would check the sleep tracker and see that I’ve not had great sleep and felt tired as a result but that’s not the case so far. It has been a hugely enlightening process incorporating the WHOOP into my life, not just for monitoring my sleep (which is a game-changer), but also for understanding science-based info on my body’s need for recovery and my high-stress triggers.

While some of the terms may seem confusing at first, the app breaks them down in a clear and concise way. The entire user face is helpfully colour-coded with graphs and packed with articles for those who wish to delve further.

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WHOOP 4.0

A balance of sleep, strain and recovery is essential to optimise your body’s performance and it’s these elements that the WHOOP pays close attention to. Disguised in a seemingly minimal black strap is a hi-tech wearable that connects via an app to reveal a wealth of data about the quality of your dozing, physical exertion and how effectively your body is able to bounce back - all of which are recorded via five LED sensors adorned on your wrist.

Given the seal of approval from professional athletes like LeBron James, Rory McIlroy and Michael Phelps, WHOOP has been proven through studies to positively change behaviour, ensure sleep is prioritised and improve physiological biomarkers.

Buy now £229.00, WHOOP

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