The effects of short, disrupted sleep on metabolic and vascular responses to exercise.

PURPOSE: The purpose of the present investigation was to determine the effects of short, disrupted sleep on postprandial lipemia and brachial artery flow-mediated dilation (FMD) after high-intensity interval exercise (HIIE). METHODS: Fifteen men (Age = 31 ± 5 years; BMI = 25.8 ± 2.7 kg/m²; %BF = 21.0 ± 6.2; VO₂ max = 49.1 ± 0.7) participated in 3 experimental conditions: reference sleep (REFSL); reference sleep and HIIE (REFEX), and; short disrupted sleep and HIIE (SLPEX). HIIE was completed at 90% and 40% of VO₂ reserve in a 3:2 ratio to expend 500 kcals. Both exercise sessions were completed in the morning after a 12-hour overnight fast. Blood samples were taken before and after exercise, immediately before, and 2, 4, and 6 hours after a commercially available high-fat meal (1,309 kcals, 88 g fat, 94 g carbohydrate, 35 g protein). Serum samples were measured for triglyceride (TG) concentrations. Total (AUCT) and incremental area under the curve (AUCI) TG were calculated and analyzed using within-subjects, repeated measures ANOVAs. Statistical significance was set at p ≤ 0.05. RESULTS: Compared to REFSL, TG concentrations, TG AUCT, and TG AUCI remained refractory to exercise. FMD was augmented 1 hour after exercise in REFEX and SLPEX compared to REFSL, and (p = 0.0494) and returned to baseline at 4 hours post-meal. HIIE did not reduce TG levels and did not modify TG AUCT and TG AUCI. Short, disrupted sleep did not influence these responses. HIIE transiently augments brachial FMD and this response is not modified by a single night of short, disrupted sleep. The short-term benefits of exercise on vascular function are resilient to after a single episode of short, disrupted sleep.