Associations of objectively measured physical activity and sedentary behavior with sleep quality in college students.

Background: Sleep disorders are prevalent in college students and are often exacerbated by academic pressures. Accumulating evidence indicates that physical activity and sedentary behaviors exert divergent effects on sleep quality. This study aimed to investigate the associations of objectively measured physical activity and sedentary behavior with sleep quality in college students. The potential effects of substituting sedentary behavior with physical activity on sleep quality were also examined.

Methods: This cross-sectional study included 349 college students (age range: 17-25 years; 57.6 % female) recruited from Shanghai, China. Light physical activity (LPA), moderate-to-vigorous physical activity (MVPA), and sedentary behavior were objectively measured using wrist-worn accelerometers for 7 days. Sleep quality was assessed using the Pittsburgh Sleep Quality Index. A single-factor model was used to examine independent associations, whereas an isotemporal substitution model (ISM) was used to estimate the effects of replacing sedentary behavior with physical activity on sleep quality.

Results: Higher levels of LPA (B = -0.007, 95 % CI = -0.013 to -0.001, p < 0.05) and MVPA (B = -0.013, 95 % CI = -0.022 to -0.003, p < 0.05) were associated with better sleep quality. Conversely, sedentary time was negatively associated with sleep quality (B = 0.007, 95 % CI = 0.002 to 0.012, p < 0.05). In the ISM, replacing 30 min of sedentary behavior with an equivalent duration of MVPA was associated with improved sleep quality (B = -0.322, 95 % CI = -0.624 to -0.021, p < 0.05).

Conclusions: The findings indicated that physical activity was positively associated with sleep quality, whereas sedentary time was negatively associated with sleep quality in college students. Replacing sedentary behavior with an equivalent duration of MVPA positively affected sleep quality.