The Effect of Lightweight Shoes on Air Force Basic Training Injuries: A Randomized Controlled Trial

Abstract

ABSTRACT Introduction/Purpose Bone stress injuries (BSI) are a leading medical diagnosis and cause of training disruptions and increased costs in US Air Force basic military training (BMT). Currently, as required by law, all trainees are issued athletic shoes upon arrival to BMT; however, the issued shoes are often disliked by trainees and are suspected of contributing to injury. This study investigated the effect of issuing shoes with lighter weight, lower heel-to-toe drop, and wider toe box than the standard-issue shoes to compare comfort, musculoskeletal injuries, and training outcomes. Methods In this blinded, randomized controlled product evaluation, trainees of a single BMT squadron were issued either the standard-issue shoes or a lighter-weight alternative; following completion of BMT, male and female cohorts were compared for differences in fitness assessment results, musculoskeletal injuries, and graduation delays using routinely collected databases. Associations between categorical variables were analyzed using a chi-square test with significance set to α ≤ 0.05. Results Among male trainees, issuing the lighter-weight shoe resulted in an absolute risk reduction of 6.05% (from 13.87% to 7.82%) and a relative risk reduction of 43.62% for BSI. Also, trainees who received the heavier standard-issue shoes noted the shoes to be “too uncomfortable to wear” at a significantly higher rate. Conclusion Issuing shoes with lighter weight, smaller heel-to-toe drop, and wider toe box appears to reduce the risk of BSI and shoe dissatisfaction among male BMT trainees; such shoe characteristics should be considered for use in populations engaging in similar physical training.