Introduction: Previous research has examined sleep restriction (SR) in relation to increased daily caloric intake, suggesting that chronic SR is a significant risk factor for weight gain and obesity. However, few studies have examined behavioral factors that contribute to this weight gain, and no studies have differentiated chronic SR vs. short term SR on these measures. We examined behavioral self-report measures among participants who engage in chronic natural sleep restriction (NSR) and participants who are experimentally sleep restricted (ESR) to elucidate these underlying differences.
Methods: Twelve female participants completed a screening interview to assess for psychopathology and sleep disorders. Participants were then assigned to either an NSR (n=6) or ESR (n=6) group based on sleep diary measures and one week of actigraphy monitoring. NSR participants averaged less than 7 hours TST, and ESR participants averaged between 7–9 hours TST. ESR participants then decreased their TST by 90 minutes per night for 1 week. Self-reported behavioral measures evaluating food consumption, appetite, and exercise duration (vigorous, moderate, and light intensity) were collected for both groups during the monitoring week and for the ESR group during the experimental week.
Results: Findings suggest no significant differences between ESR and NSR groups based on subjective measures of food consumption (U=17.5,n1 =n2 =6,p=.936) and appetite (U=7.5,n1 =n2 =6,p=.087) during monitoring week. No significant differences were observed between groups when comparing final day NSR ratings during monitoring week with final day ESR ratings during SR week for food consumption (Z=-.736, n=6,p=.461) or appetite (Z=-.816,n=6,p=.414). Lastly, no significant differences were found between groups based on self-reported exercise duration (vigorous intensity: NSRM=8.25,SD=6.43,ESRM=13.93,SD=13.54,t=-.928, moderate intensity: NSRM=10.44,SD=9.72,ESRM=11.43,SD=8.79,t=-.185, and light intensity: NSRM=49.14,SD=34.54,ESRM=26.67,SD=11.73,t=1.509; all p>.18).
Conclusion: Contrary to previous research examining these measures, no differences were found between the NSR and ESR groups. Results suggest that weight gain secondary to sleep restriction, both chronic and short term, may not be the result of behavioral changes. Given these preliminary non-significant findings, further evaluation of the sample is being conducted currently through an examination of changes in participant concentrations of ghrelin and leptin; which are hunger and satiety biomarkers. Support (If Any): NSU President’s Faculty Research and Development Grant.
Available at: http://works.bepress.com/jaime-tartar/73/