Impact of Sleep Restriction on Performance in Adults

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.

Inclusion Criteria:

- BMI 25-29.9 kg/m2

- Have at least one obese parent

- Habitually sleep 7-9 hours a night

- Free of any current and past sleep and psychiatric disorders, including eating
disorders, diabetes or Cardiovascular disease (CVD) (i.e., normal scores on:
Pittsburgh Quality of Sleep Questionnaire Epworth Sleepiness Scale, Berlin
Questionnaire, Sleep Disorders Inventory Questionnaire, Beck Depression Inventory,
Composite Scale of Morningness/Eveningness, Three Factor Eating Questionnaire)

- All racial/ethnic groups

Exclusion Criteria:

- Smokers (any cigarettes or ex-smoker < 3 years)

- Neurological, medical or psychiatric disorder

- Diabetics

- Eating and/or sleep disorders

- Contraindications for MRI scanning

- Travel across time zones within 4 weeks

- History of drug and alcohol abuse

- Shift worker (or rotating shift worker)

- Caffeine intake > 300 mg/d

- Heavy equipment operators

- Commercial long-distance drivers