The more hours adults work and the more hours they spend commuting to the job, the less time they spend sleeping.
That's the finding of new research that shows the impact of work on slumber.
Adults who sleep four and a half hours or less, worked an average of 93 minutes more on weekdays and 118 minutes more on weekends than the average sleeper, a University of Pennsylvania research team found.
People sleeping 11 and a half hours or more worked an average of 143 minutes less on weekdays and 71 minutes less on weekends, they said.
Experts recommend that adults sleep between seven and eight hours a night.
Work time determines sleep time
"These cross-sectional results in a nationally representative sample suggest that compensated work time is the most potent determinant of sleep time, in which case work time should be considered an important factor when evaluating the relationship between sleep time and morbidity and mortality," lead researcher Dr Mathias Basner said.
In their study, published in the September issue of Sleep, the researchers gathered data from 47 731 respondents to the American Time Use Survey conducted in 2003, 2004 and 2005.
The 15-minute telephone survey asks people how they spent their time between 4 am the previous day and 4 am on the day of the interview, including where they were and who they were with.
Results showed that the more daytime activities a person reported, the less he or she would spend sleeping. Time at work had the strongest effect on hours of sleep, the team reported.
TV time equalled sleep time
The researchers said that the impact of travel time on sleep was unexpected and required further research to understand how people manage commute and sleep time, as well as other kinds of travel time for errands, socialising, worship and leisure activities.
Short sleep times were also related to time spent socialising, relaxing and participating in leisure activities on the weekends.
People who slept less were spending more time in education, household activities and, for people with very little sleep, watching TV.
For most people, the researchers reported that increased TV time correlated with increased sleep time. All other activities decreased in time as sleep time increased.
On weekends, people with less sleep time also spent less time watching TV than average sleepers, while people with long sleep times spent less time socialising, relaxing and participating in leisure activities.
Age also affects sleep time, the researchers said, who noted longer average sleep times at both the older and the younger ends of the age spectrum.
People between 45 and 54 years old were most likely to be working more and sleeping less. - (HealthDay News)
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