Int J Behav Med. 2026 Jul 20. doi: 10.1007/s12529-026-10480-4. Online ahead of print.
ABSTRACT
BACKGROUND: Regular physical activity (PA) improves health across various domains, reducing the risk of cardiovascular disease and certain forms of cancer while improving mental health. Despite cultural and family-oriented strengths that can support healthy lifestyle behaviors, Latinas have high rates of inactivity and are disproportionately burdened by health conditions associated with regular PA. Thus, research is needed to elucidate determinants of success in PA interventions in this population. Sleep is a health behavior that has an established bidirectional relationship to PA, yet it remains unclear how sleep may moderate PA intervention efficacy.
PURPOSE: This study examines time in bed, as a proxy for nighttime sleep duration, as a moderator of the intervention effect on PA outcomes in two randomized controlled trials among sedentary Latinas.
METHOD: We ran a series of generalized mixed effects models with subject-specific intercepts. Analyses were run separately on data from two randomized controlled trials to help establish consistency of findings across two similar participant populations.
RESULTS: Results indicated that time in bed (whether operationalized continuously or dichotomously based on sleep duration guidelines) was a significant moderator of intervention effects on PA outcomes over time, p's < 0.05. Across studies, women who reported more time in bed showed greater benefits from intervention vs. control (in study 1) and enhanced vs. original intervention (in study 2).
CONCLUSION: To our knowledge, this is the first study to examine a sleep-related measure as an effect modifier of PA intervention success. Findings suggest that sufficient sleep may allow Latinas to benefit more from PA interventions.
PMID:42477287 | DOI:10.1007/s12529-026-10480-4