Does body composition influence air force pilots' resistance to high-G acceleration? A systematic review meta-analysis

Abstract

Understanding how body composition relates to tolerance of high +Gz is important for sustaining Air Force pilot performance, yet prior studies report mixed results. This study synthesized evidence on whether differences in body composition are associated with pass/fail outcomes on G-tests in pilots and cadets. PubMed and the Cochrane Library were searched for studies published since 2014, with Google Scholar used to supplement retrieval; ten eligible articles were meta-analyzed. Using R, the authors estimated effect sizes, tested heterogeneity, explored sub-variables, and assessed publication bias. The pooled results indicated moderate associations for body mass index (BMI) (effect size 0.47) and small associations for body weight (0.26) and muscle mass (0.31) with G-test outcomes, with low-to-moderate heterogeneity across analyses. In contrast, physical fitness variables did not differ between pass and fail groups. These findings support incorporating body composition assessment into training and selection decisions, and motivate mechanistic research linking composition, physiological strain, and operational readiness.