Napping, sleep and affect in late- and short- sleeping adolescents: An actigraphy and daily diary study.

Objectives: Adolescents in the United States do not typically attain enough sleep at night due to a combination of factors, including biological maturation and academic and social commitments. This lack of sleep leads to poor cognitive, mental, and physical health outcomes. Naps may compensate for inadequate sleep, however, little is known about how napping affects nocturnal sleep and mood over time among adolescents who are poor sleepers.

Methods: The present study used daily diary and actigraphy data collected over 15days in a sample of late- and short-sleeping adolescents (n=99; M_age=15.9years; 55% Female; 46% White, 30% Black, and 24% Multiracial/Other). Multilevel modeling was utilized to examine daily associations between daytime napping and subsequent nocturnal sleep outcomes, controlling for previous night sleep. Sex was explored as a moderator.

Results: The majority of participants (76%) napped at least once during the study period, and almost one-fifth of the sample demonstrated "habitual" or frequent napping. Nap occurrence was associated with a decrease in total sleep time by 27 minutes as well as later sleep onset time that night. Later nap offset time was associated with later nocturnal sleep onset time, and longer nap duration was associated with later nocturnal sleep onset time and lower sleep efficiency. Napping was unrelated to affect. Sex did not moderate any relations between napping and nocturnal sleep or affect.

Conclusions: The findings indicate that napping is common and generally associated with worse nocturnal sleep outcomes among a sample of late- and short-sleeping adolescents.