The Association between Sleep Quality, Physical Activity, and Risk of Developing Metabolic Syndrome

Abstract

Physical inactivity and poor sleep quality have been shown to increase the risk for Metabolic Syndrome (MetS) in middle-aged and older adults. High levels of sedentary time, independent of physical activity (PA) amount, has also shown a relationship. Whether these relationships manifest at an earlier age has not been well explored. PURPOSE: To determine the independent effects of sedentary time, sleep quality, and physical activity (PA) on risk factors for MetS in young adults. METHODS: 40 young adults (age 20.2±1.7; BMI 21.2±2.6) underwent waist circumference (WC) and blood pressure (BP) measurements. Fasted blood glucose, Low Density Lipoprotein (LDL), High Density Lipoprotein (HDL), and Triglycerides (TG) were also assessed (Cardiochek Portable Blood Test System). Objective PA and sleep were measured for 7 days with an Actigraph GT3X accelerometer. Pearson correlations examined the relationship between sedentary (number of sedentary bouts, time in sedentary bouts, number of sedentary breaks, time per sedentary break, and daily average sedentary time), sleep quality (sleep onset latency, sleep efficiency, time in bed, sleep time, wake after sleep onset, number of awakenings, and time per awakening), and PA (energy expenditure, step counts, and time spent in light, moderate, moderate-vigorous, vigorous, and very vigorous PA intensities) variables with MetS risk factors (WC, BP, LDL, HDL, TG). Stepwise linear regression was used to determine the best predictors for each MetS risk factor. RESULTS: Time per sedentary bout (TSB), time per awakening (TA), step counts (SC), and moderate-vigorous PA (MVPA) were determined to have the strongest correlation with MetS variables. SC and TSB were significant predictors of WC (R2= .41; p<0.01). TA was a significant predictor of systolic BP (R2 = 0.49; p<0.01) and total MetS risk factors (R2= 0.28; p=.002). SC was the only significant predictor of HDL (R2=0.13; p=0.025). CONCLUSION: Sedentary time, PA, and sleep quality are predictive of risk factors for MetS in young adults. Therefore, interventions to decrease sedentary time as well as improve PA and sleep quality should be implemented at younger ages as well as older.