Sex-Specific Changes in Physical Performance Following Military Training: A Systematic Review

Abstract

IntroductionMen and women joining the military undergo the same training, often in mixed-sex platoons. Given the inherent physiological and physical performance differences between men and women, it is reasonable to question whether sex differences exist in the adaptation to military training and, therefore, whether sex-specific training should be employed to optimise training adaptations.ObjectiveTo systematically review the literature evaluating changes in the physical performance of men and women following military training.MethodsSix database sources were searched in addition to extensive secondary searching. Primary prospective intervention studies (all designs) evaluating physical training interventions in military populations, reporting pre- to post-training changes in physical fitness outcomes for both women and men, were included.ResultsWe screened 3966 unique records. Twenty-nine studies (n = 37 study reports) were included, most of which were conducted in the USA and evaluated initial training for military recruits. Positive changes were more consistently observed in aerobic fitness and muscle strength (whole body and upper body) outcomes than lower body strength, muscle power or muscle endurance outcomes, following physical training. Relative pre- to post-training changes for all outcome measures tended to be greater in women than men although few statistically significant sex by outcome/time interactions were observed.ConclusionImprovements in some, but not all, performance components were observed following a period of military training. Largely, these improvements were not significantly different between sexes. Further prospective research is needed to evaluate sex-specific differences in the response to physical training in controlled conditions to improve military physical training outcomes for both sexes.Electronic supplementary materialThe online version of this article (10.1007/s40279-018-0983-4) contains supplementary material, which is available to authorized users.

Changes in physical fitness and anthropometrics differ between female and male recruits during the Finnish military service

“…As in previous studies, there were significant differences in fitness level between the sexes before and after military service. The present results diverged slightly from the outcomes of Varley-Campell et al 14 . They noticed that pre-post physical training responses tended to be greater in female than male although the overall changes were minor in both sexes.…”

“…However, in a recent review article, Varley-Campbell et al 14 encouraged further studies to evaluate sex differences in response to demanding military training.…”

No Change – No Gain; The Effect of Age, Sex, Selected Genes and Training on Physiological and Performance Adaptations in Cross-Country Skiing

“…The sex differences at baseline in the present study were maintained in TT DP , RUN-VO 2max , and DP-VO 2peak from May to October due to no significant differences in training progression between males and females in this period. This may suggest that males and females do not differ in physiological and performance adaptations to a similar training pattern, which is in line with previous studies (Astorino et al, 2011;Støren et al, 2017;Varley-Campbell et al, 2018). However, sex difference in C DP declined significantly from PRE to POST1, due to a significantly improved C DP in females while the males maintained their pre-values.…”

“…Sex differences have been examined in recent years among cross-country skiers, however, sex comparisons in training responses to a similar training regimen is not well examined in well-trained cross-country skiers. Previous investigations have revealed no difference in training responses between males and females following the same training program in both sedentary and well-trained individuals (Astorino et al, 2011;Støren et al, 2017;Varley-Campbell et al, 2018), suggesting that this may also be the case for well-trained cross-country skiers. Although both junior and senior skiers have been investigated separately (Ingjer, 1992;Sandbakk et al, 2010Sandbakk et al, , 2016Losnegaard et al, 2013), direct comparisons of training responses in these age-groups have not been executed previously in cross-country skiers.…”

Understanding the musculoskeletal injury risk of women in combat: the effect of infantry training and sex on musculoskeletal injury incidence during British Army basic training

“…Women are typically at a twofold to threefold higher risk for musculoskeletal injury than men during basic military training 6 11–14. Women entering military training have lower aerobic fitness, upper-body strength, lower-body strength, and muscle mass, compared with men,3 10 31 which contribute to a higher physiological stress during military training3 32 and increase the risk of musculoskeletal injury 6 14. These proposed sex differences in physical performance and body size did not translate to a sex difference in the incidence of stress fractures during standard entrant training, likely because of the low rates of stress fracture in both men and women.…”