Background/Purpose
Research suggests a link among sleep duration, physical activity, and obesity. Sleep plays an important role in the maturation and health of youth. Therefore, the purpose of this study was to examine the relationships among sleep duration, physical activity, and BMI of Caucasian and Hispanic middle school students.
Method
Participants were 227 seventh-eighth grade students (108 boys, 119 girls; 60% Caucasian, 40% Hispanic). Sleep duration was reported in hours using the School Sleep Habits Survey. Physical activity was determined through step count and activity time. Participants wore the Walk4Life Pro pedometer for four consecutive school days, which recorded both step count and activity time. BMI was calculated using the BMI Tool for Schools.
Analysis/Results
Pearson Correlation Coefficients indicated significant, strong relationships among sleep duration, step count, and activity time regardless of ethnicity, gender, or grade. Specifically, a significant, strong relationship between sleep duration and step count was reported (0.74; p ≤ 0.01). A significant, moderate/strong relationship between sleep duration and activity time was reported among eighth grade Hispanic girls (0.66; p ≤ 0.01) and seventh grade Caucasian boys (0.76; p ≤ 0.01). There was a significant, moderate relationship between sleep duration and BMI among seventh grade Hispanic boys (-0.54; p ≤ 0.01).
Conclusions
Results present evidence that sleep duration is associated with physical activity in middle school students. With physical activity and diet interventions showing mixed results, sleep duration may be a promising variable for both physical/health education and obesity prevention efforts to examine.