Sleep Duration and Waking Activities in Relation to the National Sleep Foundation's Recommendations: An Analysis of US Population Sleep Patterns from 2015 to 2017.

The objective was to investigate the association between time spent on waking activities and nonaligned sleep duration in a representative sample of the US population. We analysed time use data from the American Time Use Survey (ATUS), 2015-2017 (N = 31,621). National Sleep Foundation (NSF) age-specific sleep recommendations were used to define recommended (aligned) sleep duration. The balanced, repeated, replicate variance estimation method was applied to the ATUS data to calculate weighted estimates. Less than half of the US population had a sleep duration that mapped onto the NSF recommendations, and alignment was higher on weekdays (45%) than at weekends (33%). The proportion sleeping longer than the recommended duration was higher than those sleeping shorter on both weekdays and weekends (p < 0.001). Time spent on work, personal care, socialising, travel, TV watching, education, and total screen time was associated with nonalignment to the sleep recommendations. In comparison to the appropriate recommended sleep group, those with a too-short sleep duration spent more time on work, travel, socialising, relaxing, and leisure. By contrast, those who slept too long spent relatively less time on each of these activities. The findings indicate that sleep duration among the US population does not map onto the NSF sleep recommendations, mostly because of a higher proportion of long sleepers compared to short sleepers. More time spent on work, travel, and socialising and relaxing activities is strongly associated with an increased risk of nonalignment to NSF sleep duration recommendations.

Waking Activities and Sleep: Analysis of United Kingdom Adolescents' Daily Time-Use Diaries.

PURPOSE: To investigate waking activities associated with risks of short and long sleep in a representative cohort of UK adolescents. METHODS: Data from 14-year-olds participating in the UK Millennium Cohort Study were used. Daily time-use diaries were completed by adolescents on two randomly selected days (one weekday and one weekend) to capture their activities within a 24-hour period from 4 a.m. of each selected day. Short and long sleep duration categories were defined as beyond the extreme lower and upper thresholds of acceptable age-specific sleep durations recommended by the National Sleep Foundation, respectively. RESULTS: Approximately 8% and 6% were short sleepers on weekdays and weekends, respectively. On average, adolescents spent 33% of their time awake per weekend day on recreational digital media activities. Compared with those who had optimal sleep on weekdays, short sleepers spent more time on personal care (mean difference = +56 minutes; 95% confidence interval [CI]: 21; 92) and less time on exercise activities (mean difference = -15 minutes; 95% CI: -27; -3). Ten-minute increase in daily digital media activity was associated with 2% (95% CI: 1.01; 1.03) higher relative risk of adolescents being short sleepers on weekdays. Relative risk of short sleeping was 1.03 (95% CI: 1.01; 1.04) times higher for every10-minute daily increase in travel time on weekdays. CONCLUSIONS: Adolescents spend up to one-third of their time awake per day on digital media. However, more time spent on personal care and travel on weekdays and weekends is associated with increased risk of short sleep. These findings permit a reflection on appropriate interventions needed to improve sleep duration in sleep-deprived teens.