The Effect of Sleep Deprivation and Moderate Intermittent Exercise on Maximal Aerobic Capacity

The purpose of this study was to determine the effects of moderate intermittent work (IW), partial sleep deprivation (PSD) and 8 hrs. of recovery sleep (RS) on maximal oxygen uptake (VO2max). The IW consisted of two 20 hr. periods separated by a 3 hr. nap. Thirty male subjects with the following mean characteristics (age = 21.2 yrs., height = 176.6 cm., and weight = 74.9 kg.) were randomly assigned to a non-exercising group (C), or an exercising group (E). Subjects were further randomly assigned to Noon (N) or Midnight (M) start times. Comparisons of low (L) and high (H) fitness levels based on baseline VO2max were also made. All groups underwent PSD with E walking on a treadmill at 30% of VO2max for 30 mins/hr. VO2-max, maximum heart rate (HRmax) and maximal treadmill walk times (WT) were measured three times; baseline (T1), after IW (T2) and after RS (T3). The L and H means for VO2max were 45.7 and 54.3 ml/kg/min, respectively, while all other group means were within 2 ml/kg/min of 50 ml/kg/min, STPD. Following PSD VO2max dropped 3.5% in C and increased 2.5% in E (P 0.05). The HRmax means were within 5 bts/min of 197/min for all groups, and the means WTs were between 12.0 and 12.8 mins. with only the H and M groups demonstrating with means of 13.4 and 13.3 mins., respectively. The changes in C and E following PSD support the hypothesis that moderate IW counteracts PSD C and E following PSD induced decrements in VO2max. Neither fitness level nor start time altered the effects of PSD on VO2max. Keywords: Physical fitness.