Fitness trackers

Sleep experts said that thousands of people use fitness trackers such as Fitbit and Jawbone to monitor their sleep just as they measure the steps they take during the day, which can turn us into a nation of insomniacs.
A sleep specialist Professor Paul Gringras said he could not foind a cheap version of the device which can be fully relied upon, adding that judging sleep by how much people move, they often get it wrong.
The trackers push people to set sleep goals and fixate on how many hours they get. Professor Gringras said: ‘People are not helped by assuming an average of say eight hours’ sleep is a target which has to apply to everyone … fitness trackers may make it worse.
‘Someone might not have been worrying about their sleep, but then they buy something which claims to be accurate which tells them they are not sleeping well and it can trigger anxieties about sleep and start a difficult cycle.