Effect of Long Term Sleep Restriction on Energy Balance

Chronic Sleep Restriction (SR) is highly prevalent in today's modern society. Artificial light, portable electronic devices, and 24-h services have allowed individuals to remain active throughout the night, leading to reductions in sleep duration. SSD has been linked to obesity and our laboratory has been interested in establishing whether sleep could be a causal factor in the etiology of obesity. Given the increasing prevalence of obesity over the past 5 decades, coinciding with the marked reduction in sleep duration, further exploration into the role of sleep as a risk factor for obesity could provide additional ammunition in the fight to prevent further increases in the incidence of obesity.

This study will be a randomized, crossover, outpatient SR study with 2 phases of 6 weeks each, with a 6 week wash-out period between the phases. Sleep duration in each phase will be the participant's regular bed- and wake times during the habitual sleep (HS) phase and HS minus 1.5 hours in the SR phase. During the HS phase, participants will be asked to follow a fixed bedtime routine based on their screening sleep schedule. During the SR phase, participants will be asked to keep their habitual wake time constant but delay their bedtime to achieve a reduction of 1.5 hours in total sleep time.