Nurses who work the longest hours tend to get the least sleep, a US study suggests.
Telephone interviews conducted on more than 47,000 people in the US between 2003 and 2005 shows waking activities are inversely related to sleep time.
The activity with the largest influence on sleep time was work. Respondents who slept 4.5 hours or less worked an average of 93 minutes more on weekdays and 118 minutes more on weekends than the average sleeper.
Those who slept 11.5 hours or more worked an average of 143 minutes less on weekdays and 71 minutes less on weekends.
Commute time at weekends and weekdays also influenced the amount of sleep people got.