Is tracking shut-eye time well spent?
Are cyclists sleepwalking into information overload, asks Lexie Williamson
As a keen cyclist and occasional insomniac, I’ve got into the habit of delving straight into my sleep data as soon as I wake up. Take this morning: in a few seconds, data from my Garmin watch downloaded onto my phone showing eight hours, 32 minutes of sleep, of which 39 minutes were ‘deep’, five minutes were ‘light’ and two hours 38 minutes were REM. I flicked down to my ‘sleep score’ – a rating of sleep on a scale of zero to 100 – to see a score of 82 (‘good’), indicating that I was adequately rested for the hard interval turbo session I had planned for later. Obsessing over this data is a hard habit to break.
I’m not alone. As cyclists we’re accustomed to arriving home, unclipping, and scrutinising our ride data.
An increasing number of us are also monitoring what happens when we’re tucked up in bed, using wearables that record our sleep and other recovery data such as heart rate (HR) and heart rate variability (HRV), the variance in time between heartbeats. The aim is to gather not only data on how hard you are pushing on the bike, but also how well your body is recovering afterwards – helping to guide your workload for the next day.
The brands behind the trackers are keen to forge a connection with the cycling community. Whoop sponsors the EF Education-EasyPost team and world champion Matheiu van der Poel, while Ultrahuman makes the Air ring worn by Tadej Pogačar and his fellow UAE Team Emirates riders. At the upcoming Tour de France, EF will also use the Eight Sleep Pod, a cooling mattress topper, placed on riders’ beds to lower body temperature and collect sleep data.
While sleep data may be useful for micromanaging the health of pro riders, can it help normal riders like you and me? The trackers claim to measure the quality of sleep, quantify ‘readiness’ to ride and alert us to possible illness, but are they accurate? What’s more, could it be a case of too much information adding to mental pressures and actually making it harder to sleep? To find out, I decided to test a Whoop band and Ultrahuman’s Air ring.
Before we get to the testing, let’s explore how these wearables work. Sleep is characterised by a range of physiological changes in brain activity, heart rate, blood pressure, body temperature, respiration, eye movement and muscle tone. Measuring sleep in the gold standard polysomnographic (PSG) laboratory test, a team of professionals use a montage of electrodes to capture these changes. Wearables, meanwhile, pick up some of these changes, such as HR and HRV by shining a light through the skin to detect blood flow changes.
They detect temperature and al
