Within-person, prospective relations between sleep duration and efficiency and next-day physical activity among...

Behavioral weight loss programs (BWL) prescribe moderate-to-vigorous physical activity (MVPA) to promote weight control and overall health. However, adherence to the MVPA prescription is low. One factor that may be associated with poor MVPA adherence, both theoretically and as demonstrated by between-subject studies, is suboptimal sleep. Nevertheless, no study to date has examined the within-subject relations between sleep and MVPA among BWL participants, which could better account for between-subject third variables that may confound the relation between sleep and MVPA (e.g., socioeconomic status). This secondary analysis is the first to investigate the within-subject, prospective relations between sleep duration (controlling for time in bed) and sleep quality (operationalized as sleep efficiency, approximately minutes asleep divided by time in bed) with next-day MVPA among BWL participants.

Participants (N = 104) were adults with overweight/obesity engaging in a year-long BWL program. Sleep variables and MVPA bouts were measured using accelerometers at mid-treatment. Predictor variables were standardized, and analyses were conducted using multilevel models, controlling for weekday/weekend status, condition, gender, and body mass index (BMI).

Results indicated within-subject sleep duration (b = 15.48, SE = 6.30, p =.014), but not sleep efficiency (b = 2.16, SE = 1.22, p =.08), was positively associated with next-day minutes of MVPA.

Findings may support modifications of BWL programs to include sleep hygiene education or strategies from cognitive behavioral therapy for insomnia to target sleep duration, which in turn may improve MVPA engagement.