The Effects of Sleep Loss on Military Physical Performance

As part of both training and active service, military members can be exposed to prolonged periods of sleep loss. Given the extent of physical and cognitive performances viewed as critical to successful military performance, such sleep disruption may present risk to health and performance. The primary aim of this narrative review was to investigate evidence on the effect of inadequate sleep on measures of aerobic capacity, anaerobic capacity, muscular strength and muscular endurance in military personnel. Sleep loss appears to have the greatest negative impact on aerobic capacity, muscular endurance and military-specific performance in military populations. The findings showed varied results for handgrip strength and anaerobic capacity, with sleep loss inducing a decrease in mean power of the upper body. In comparison to other measures of performance, lower-body muscular strength appeared to be resilient to sleep restriction. However, due to the limited evidence and inter-individual variability in results there is no clear consensus on the specific volume of sleep loss that induces significant or meaningful performance decrements. The difficulties of conducting well-designed and -controlled interventions in military populations are appreciated. However, due to the low quality of reporting and lack of control for confounders (i.e. physical activity, load carriage, prior sleep debt, motivation and energy intake) in the majority of studies, it is difficult to establish the relationship between sleep loss and physical performance in military populations.