How Whoop's Health Monitor guided me through a nasty bug

How to use and interpret this under-rated Whoop feature
Wareable How Whoop Health Monitor guided me through a nasty bug photo 3
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One of my favorite Whoop features is Health Monitor, and once again, it’s just come to my rescue.

Health Monitor is a daily overview of your general well-being via five core metrics: resting heart rate, breathing rate, skin temperature, heart rate variability (HRV), and blood oxygen.

If you get ill (or experience the effects of lifestyle factors such as overtraining or being hungover) they will show up in these stats. So as I was taken down by a family stomach bug last week, there was unsurprisingly a huge change in these stats (see below)

This is the basis of a new Oura Labs Symptom Tracker too, and we've also seen similar implementations in the Fitbit Health Metrics Dashboard, too.

How Health Monitor works

WareableHow Whoop Health Monitor guided me through a nasty bug photo 4

Whoop takes a reading for the following metrics every night when you sleep. This ensures consistency in the readings, which means a baseline can be taken, which is your normal range. Whoop takes 30 days to calculate this, and it’s average on an ongoing basis.

Each morning, it shows last night’s reading, and whether it’s within a ‘normal range’ – if so it’s presented as green. If it’s slightly high/low it will be marked as amber. If it’s really out of the ordinary, it will be marked red.

You can see the effect of the virus I picked up in the stats above.

Resting heart rate – a measure of wellness and fitness. Spikes in resting heart rate are linked to illness, fatigue stress, or lifestyle factors (hangovers).

Breathing rate – breaths per minute are usually stoically steady unless you get ill. Even small changes (perhaps two breaths per minute) represent a sizeable change in your physiology and show something is up.

Skin temperature – everyone knows this can spike when you get ill, so watch out for changes here. Can also be triggered by Whoop being trapped under your body for example, so look for other changes too.

Heart rate variability (HRV) – this underpins most of Whoop’s systems. Rises are usually linked to good habits and lifestyle factor, and low scores mean fatigue, stress or illness. Isn’t infallible, however (see below).

Blood oxygen – can show the effects of altitude or respiratory problems.

Find out how ill you are

WareableHow Whoop Health Monitor guided me through a nasty bug photo 4

When you wake up and feel not yourself, the Health Monitor stats can be a useful interpretation of how ill you are.

Most minor colds won’t move the needle much, so if I have a sniffle and the stats are steady, it usually gives me the confidence it’s going to be simple to shake. I might even still work out lightly, etc.

But if those stats go out of range with red or amber warnings – I know it's time to get serious. 

Watch out for abnormally high HRV

WareableHow Whoop Health Monitor guided me through a nasty bug photo 4

Whoop’s HRV readings are excellent and underpin the Recovery score. But your body’s HRV can be tricky when the chips are down.

When your body suffers extreme stress, HRV can rebound to create abnormally high readings.

As you can see, my body should have been eliciting a recovery score of around 1-10%, but the absurdly high HRV tricked Whoop into recording scores of 70%-90% before it plummeted.

It shows that rarely can you rely on one metric, but it’s something Whoop should better factor into its algorithms.

The road to recovery

WareableHow Whoop Health Monitor guided me through a nasty bug photo 4

This addresses something of the ‘so what?’ question. Feeling ill and seeing abnormal stats can be interesting – but it hasn’t told us much we didn’t already know.

Where this data gets interesting – in my mind – is around recovery.

As you start to get better, your stats will start to move back towards your baselines. As you can see from my stats above, resting HR shot up, and then slowly reverted back to normal.

Likewise, breathing rate did too. But even as I type this, that's not back to baseline, so I'm not back to full recovery yet.

That process can be slower than you might like, and realizing and accepting that can make life easier.

These stats can encourage you to give yourself a break in terms of expectations of what you can and should do as you get back to health.

I was frustrated for not feeling myself and not wanting to work out 5 days after the bug took hold. But the fact that my breathing rate was still elevated – significantly above my normal range – helped validate that it was OK not to feel normal.

Likewise, seeing your health return can offer a sense of progress, even while you’re ill. I’m sure I’m not the only person who feels like life has ground to a halt, whiling away the hours in bed, or struggling to look after kids while enduring illness.

Seeing the stats returning offers reassurance and patience that there’s no need to rush things and that your body is handling things just the way it should.

1. Ask Whoop Coach

You can ask the Whoop Coach AI things like “track my respiration rate over the last week” or “show my resting heart rate trends” and it will pull the data for you. It’s a quick way of showing your core stats.

The chat box is on most pages of the Whoop app – including the Overview tab.

2. See Trend graphs:

On the Overview screen scroll down to where it says Key Statistics. Tap any of these, and you’ll go to the Trend View screen.

You can choose any metric to see this plotted over a week, month or six month period.

You can also choose Customize and then have these displayed on the Overview tab permanently.

Proactive wearables

The Whoop Health Monitor is one of the more proactive systems out there, with its traffic light system and warnings of elevated stats.

But it stops short of interpreting these stats and offering advice towards recovery.

It doesn’t link poor sleep, to out-of-range metrics to even tagging “feeling sick or ill” within the Whoop Journal. It doesn’t let you tag symptoms, or link these to the metrics captured.

So there’s a way to go to make Health Monitor a true illness detection system, which could even track the effectiveness and speed of your recovery.

But this is a great start.

How we test

James Stables


James is the co-founder of Wareable, and he has been a technology journalist for 15 years.

He started his career at Future Publishing, James became the features editor of T3 Magazine and and was a regular contributor to TechRadar – before leaving Future Publishing to found Wareable in 2014.

James has been at the helm of Wareable since 2014 and has become one of the leading experts in wearable technologies globally. He has reviewed, tested, and covered pretty much every wearable on the market, and is passionate about the evolving industry, and wearables helping people achieve healthier and happier lives.

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