Fitbit's sleep tracking explained

How to stop poor sleep becoming a handbrake on your emotional wellbeing
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Fitbit’s approach is not only to understand your sleep, but to also improve it. And thanks to Fitbit's range of heart rate sensing fitness devices, it's able to analyse your sleep in-depth, and offer tools to improve rest.

Clinical mental health therapist and sleep specialist Natalie Pennicotte-Collier says that poor sleep can act as a "handbrake on your emotional wellbeing" – but some people don't realise their Fitbit is producing actionable data on what's happening to your mind and body during those night time hours.

We teamed up with Natalie to find out how your Fitbit can help you sleep better in 2020.

1. Use Sleep Stages to understand your body

Fitbit's sleep tracking explained

When it comes to activity tracking, Fitbit has a whole range of wearables tailored to suit different needs. But one feature that runs through Fitbit’s heart rate tracking devices is Sleep Stages – something that basic trackers just can’t do.

Fitbit is able to detect how long you spend asleep. The more time asleep means more opportunity to touch on all the nourishing stages of sleep: light sleep, REM and deep sleep. This is monitored through a combination of your heart rate data and motion detection and forms Fitbit’s Sleep Stages.

The Fitbit app presents your transition through each sleep cycle as what Natalie calls “mini staircases” you can quickly check in on how your body was resting.

“Sleep Stages are a unique signature. It’s incorrect to say everyone should have 3 hours 46 minutes of deep sleep, for example. Just having the knowledge and sleep science doesn’t necessarily get you to change your habits,” Natalie said.

Five of these staircases equates to approximately 7.5 hours of sleep in a night, but again it’s important to not get bogged down in numbers as every sleep signature is distinct. If your body isn't cycling through stages, then it's an indication there's something wrong.

2. React to your Sleep Score

Fitbit's sleep tracking explained

The Fitbit app takes your sleep duration, sleep depth and sleep restoration data and forms a Sleep Score – a single number that's easier to understand.

It's a score out of 100 and assigned ratings such as ‘Excellent’ and ‘Good’. This forms the basis of how Fitbit is making sleep easier to understand. The score is tracked over time, which makes it easier to take positive steps to improve it.

“I've been sleeping at altitude recently, and my Sleep Score has gone down shockingly. It’s normally between 80-90 and now it’s down at 68 because my sleep is so fragmented," Natalie said.

"So for the last two days I’ve been taking power naps when I can. Not all night’s sleep is the same. You need to skilfully respond to changes in Sleep Score.”

Changes could be making more time for naps, reducing caffeine and screen times, reading before bed – or using other elements of the Fitbit app. This could be using the Discover section of the app, where there's mindfulness audio content and other apps to explore.

3. Use Fitbit to boost sleep consistency

Fitbit's sleep tracking explained

Staying consistent helps your body work alongside its natural biological clock, and this can have a positive impact on bodily functions from digestion to immunity.

For this reason, to build positive sleep habits, it’s important you avoid hitting that snooze button in the morning so that you start the day right.

“A good night’s sleep starts the moment when we wake up. It’s what we do during the day that will mirror image - more often than not - the quality of sleep we have in the evening," said Natalie.
“A good night’s sleep starts the moment when we wake up

Using your Fitbit, you can correlate your wellbeing and behaviour habits during the day. You can directly see each night the impact of that”

Natalie says that one of the most effective steps you can take towards a better night’s sleep is getting a constant wake time – and this is where Fitbit’s Sleep Schedule feature comes in.
"This helps you keep track of your bed and wake times over the week, so you can gun for better consistency. It’s the baseline. That’s the one thing you can control. What time you go to sleep and what time you get up.”

“It’s absolutely crucial to have consistency when you come into the period with the most cortisol [the stress hormone] in the day. Even more so than the time you go to bed."

4. Use the guided breathing exercises

Fitbit's sleep tracking explained

Natalie is a big fan in particular of the guided breathing exercises within the Relax feature on Fitbit devices such as the Charge 3, Versa 2 and Ionic, as a means to reducing stress during the day.

“Having habits of good sleep, you can only have that by tracking and seeing the impact of what you do during the day, how well rested you are. What happens when you spend more time in the guided breath element, what does that do for me specifically?”

5. Go Premium for more data

Fitbit's sleep tracking explained

While all of the above is available as standard in the Fitbit app, you can unlock more in-depth features through a Fitbit Premium subscription. This will appeal to anyone who wants to gain an even greater understanding of their sleep alongside a raft of other extra features including health and fitness guidance and dynamic workouts.
You’ll gain access to a Sleep Score Breakdown, which is a deep dive into your daily Sleep Score showing precisely how it was calculated based on your unique sleep stages and restoration measurement. This gives you a greater understanding of areas you can look to improve.
You’ll also unlock the ability to view your heart rate throughout the night, which will give you a greater understanding of the restorative effect of your night’s sleep.

6. Use Guided Sleep Programs

Fitbit's sleep tracking explained

Guided Sleep Programs are Fitbit Premium’s step-by-step guides to changes you can make towards a better night’s rest. These include a personal bedtime routine checklist, as well as soothing audio tracks for unwinding and helping you to fall asleep.

Going through each sleep program – such as Get More Zzz's, lasts a few weeks and they’re always on hand to repeat if your sleep habits ever need a tune up.

Then there are the Personalised Sleep Insights.

These pull together everything Fitbit is tracking about you, from your activity levels during the day, bedtime routine and resting heart rate, and turns this into tailor-made guidance so you can improve your overall wellbeing.


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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