Want to know how your smartwatch measures your heart rate? Well, the next thing you should watch is this video I made with the amazing @SteveMould!    • The bizarre flashing lights on a smar...  

And these videos are both part of my Smartwatches series. Check out all the instalments here!    • Smartwatches series  

Smartwatches make some grand claims, counting steps, heartbeats and sleep, and offering insights into our health and wellness. But how accurate are the numbers? Which is the best smartwatch? (Out of these three, anyway…) Using the latest scientific research (and some of my own experiments!), I ask: can you trust your smartwatch?

In this video, I pit an Apple Watch SE, a Fitbit and a Mi Band 6 against one-another. Obviously there are lots more brands on the market (Garmin, Huawei, Oura Rings and many more!) and if I had a bit more budget it would be great to do a more comprehensive comparison of their accuracy. One day… :)

Chapters

00:00 Introduction
00:31 Counting steps
04:56 Heart rate during exercise
07:40 Heart rate: all day
09:01 Heart rate: all night
10:47 It knows when you are sleeping…
13:12 Conclusion

Sources and further reading

Steps
‘Accuracy of Fitbit devices: Systematic review and narrative syntheses of quantitative data’ https://mhealth.jmir.org/2018/8/e10527

Heart rate
‘Investigating sources of inaccuracy in wearable optical heart rate sensors’: https://www.nature.com/articles/s4174...
Study comparing the Polar H10 to research-grade equipment, finding that it’s suitable for use as a ‘gold standard’: https://pubmed.ncbi.nlm.nih.gov/31004...
Did I mention the video I made with @SteveMould?!    • The bizarre flashing lights on a smar...  

Sleep
Systematic review of Fitbit sleep analysis: https://www.ncbi.nlm.nih.gov/pmc/arti...
Two more articles looking at different devices’ sleep performance: https://www.ncbi.nlm.nih.gov/pmc/arti... https://www.dovepress.com/evaluations...
Apple Watch sleep stage tracking performance from @TheQuantifiedScientist:    • Apple Watch SE 2022 : Full Scientific...  

White dudes
‘Limiting racial disparities and bias for wearable devices in health science research’: https://academic.oup.com/sleep/articl... (I’m going to make a full video about this at some point but it would be remiss not to at least include an introductory link…)

Credits

Thanks to Tran Nguyen for filming and letting me take her expensive doctor stethoscope to Steve’s studio, and thanks to Linh for letting me borrow her Apple Watch for testing!

And finally…

Follow me on Twitter   / statto  
Follow me on Instagram   / andrewjsteele  
Like my page on Facebook   / drandrewsteele  
Follow me on Mastodon https://mas.to/@statto
Read my book, Ageless: The new science of getting older without getting old https://ageless.link/