American adults might be better off watching less television and playing fewer video games and instead getting more sleep, according to two presentations this week in Seattle at SLEEP 2009, the 23rd Annual Meeting of the Associated Professional Sleep Societies.

"Previous research on computer gaming has been done primarily on adolescents and children, so we wanted to explore the impact of gaming on an older population," Amanda Woolems, at the University of Arkansas in Little Rock, told Reuters Health.

Woolems and her associates studied 137 university students; 51 were male, and the average age was 22.3 years old. According to questionnaire responses, 10.8 percent of those who played computer games reported that gaming interfered with their sleep, and 12.6 percent identified themselves as being "addicted" to gaming.

Compared with other gamers, these two groups had more maladaptive sleep hygiene and slept an average of 1.0-1.6 hours less on weekdays.

By analyzing individual Sleep Hygiene Indexes, the researchers observed that "gamers scored high on going to bed at different times; doing something that may wake them up before bedtime; going to bed feeling stressed, angry, upset, or nervous; and thinking, planning, and worrying in bed."

Furthermore, Woolems added, "Excessive gamers (those who played console/computer games more than 7 hours a week) had significantly poorer sleep hygiene than other gamers and slept less on weekdays. This is consistent with a study on adolescents that suggests gaming be limited to 1 hour per day to improve sleep hygiene and sleep time."

Relaxing though it may be, watching television may be another pastime that cuts into valuable sleep time, particularly among individuals who work long hours, according to Drs. Mathias Basner and David F. Dinges from the University of Pennsylvania School of Medicine in Philadelphia.

"Sleeping less than 7-8 hours daily impairs alertness and is associated with increased obesity, morbidity and mortality," they write in their meeting abstract. "Yet 40 percent of U.S. adults do so."

"People who sleep very few hours per day trade sleep time for other waking activity time," Basner told Reuters Health. "We looked at what activities they exchange for sleep."

The researchers analyzed data from the American Time Use Survey for 2003-2006, which included 23,791 respondents age 15 and older. The results showed that, on average, those who worked 8 hours a day or more arose in the morning 40 minutes earlier than people who worked fewer hours, and nearly an hour and a half earlier than non-workers.

"Astonishingly," Basner said, "the time at which long-workers went to bed did not differ at all from those who worked less or didn't work at all." Watching TV accounted for nearly half of the 2-hour pre-sleep period.

He and his colleague theorize that watching television may be an important "social Zeitgeber" (cue) for the time of going to bed.

"Long-workers watch 50 minutes of TV in the evening, but they should use some of that time to go to bed a little earlier and get enough sleep," Basner concluded. "Right now, I don't think there is any awareness of the importance of adequate sleep."