Work time is the single most important lifestyle factor that impacts on sleep - the more hours you work the less sleep you get - research suggests. Those who got less than four-and-a-half hours sleep a night worked an average of 93 minutes longer on weekdays and 118 minutes more on the weekend. Commuting time ranked second, above socialising and leisure time.
The study in the journal Sleep included nearly 50,000 US participants, a private channel reported. They were surveyed on three different occasions - in 2003, 2004 and 2005 - and asked how they spent their time between 4 am, the previous day and 4 am that day. Time spent working had the biggest impact on sleep time. Those who slept 11-and-a-half hours or more worked an average of 143 minutes less on weekdays and 71 minutes less on weekends than the average sleeper.