Effect of one night of sleep deprivation on maximal fat oxidation during graded exercise

Abstract

The aim of this study was to investigate the effects of one night of sleep deprivation on maximal fat oxidation during a graded exercise test. Ten healthy young males underwent two 2-day control and sleep deprivation trials. Participants were allowed normal sleep from 2300 to 0700 for the control trial, whereas they were required to stay awake for 34 h during the sleep deprivation trial. At 1700 on day 2, participants performed a graded exercise test to exhaustion on a treadmill; this allowed us to determine maximal oxygen uptake and maximal fat oxidation. Before and immediately after the graded exercise test, blood samples were collected in order to measure glucose, insulin, free fatty acid, and triglyceride concentrations. Plasma glucose concentrations were significantly higher in the sleep deprivation trial than in the control trial before the graded exercise test. Serum insulin and free fatty acid concentrations were not significantly different between the two trials. Serum triglyceride concentrations were significantly lower in the sleep deprivation trial than in the control trial. The maximal fat oxidation rate, oxygen uptake, and heart rate at maximal fat oxidation intensity, during the graded exercise test, were not significantly different between the two trials. These findings suggest that maximal fat oxidation during graded exercise is unaffected by one night of sleep deprivation.

Keywords

• sleep loss
• insulin
• glucose
• exercise