Relationship between actigraphy-assessed XXXX and fat mass in college students.

@entity1 @entity25 @entity28
OBJECTIVE: Only a few studies have used objective measurements to investigate the relationship between @entity25 and @entity28 . These studies showed controversial results. METHODS: Sleep efficiency was measured by Actiwatch 2 in 132 healthy students (age 23.3        3.7 years, BMI 23.1        4.1 kg/m(2) ) for 12        3 nights, differentiating between work and free days. Physical activity, dietary habits, and autonomic function (heart rate variability, HRV) were analyzed as potential determinants of @entity25 and its relationship with body composition. RESULTS: Sleep efficiency was 87.0% in @entity1 and 84.9% in @entity1 (P   <   0.05) and was higher at free days when compared to work days in @entity1 (P   <   0.05). @entity25 was associated with a higher fat mass. This was true for sleep efficiency on work days in @entity1 [fat mass index (FMI): r   =   -0.35, P   <   0.01] and for free days in @entity1 (FMI: r   =   -0.37, P   <   0.05). Poor sleep efficiency was associated with less physical activity (r   =   0.29, P   <   0.05) and impaired HRV in @entity1 (r   =   0.60, P   <   0.05) and with a higher fat intake in @entity1 (r   =   -0.39, P   <   0.05). CONCLUSIONS: Poor sleep efficiency was associated with higher fat mass. The relationship between @entity25 and fat mass differs between work and free days and may be explained by physical activity and autonomic function in @entity1 and dietary habits in @entity1 .
