Characterizing Reproductive Health and Performance Outcomes in Female Canadian Armed Forces Members with a History of Lower Body Injuries

Abstract

Female representation in the Canadian Armed Forces (CAF) is at the highest it has been (16.48%) since women were allowed to integrate in 1965. While the sex ratio is similar to our allies, the government of Canada aims to increase the female membership to 25% by 2026 and have prioritised identifying avenues to increase recruitment and retention. Musculoskeletal injuries (MSKi), specifically repetitive strain injuries (RSI), are a leading cause of attrition in female service members of the CAF. Understanding what health and performance factors are associated with the increased attrition related to RSIs may help further the knowledge that can support female service members throughout each phase of their career. This thesis undertook two studies that aimed to uncover how reproductive health and lower body performance was associated with lower body RSI. The goal of the first study was to ascertain if female reproductive health characteristics (i.e., irregular menstruation, hormonal birth control use, late age of menarche, parity) were associated with lower body RSI (e.g., knee, ankle, foot, etc.), and if so, which ones. Cross-sectional data were collected via questionnaire from n=2,001 (female n=855) service members of the CAF. Females who had reported experiencing irregular menstruation were more likely to report having sustained a hip, knee, or lower leg RSI, while those having given birth reported RSIs of the foot more often. The objective of the second study was to see whether previous RSI in the lower body was associated with poorer lower body physical performance compared to those who had not sustained a previous lower body RSI. A set of 90 female service members underwent a series of tasks such as, sit-and-reach, long jump, back squat, wall-sit, and treadmill VO2max. Female service members who reported a previous ankle RSI were found to be associated with higher VO2max compared to those not reporting ankle RSI. Together, the results of the thesis demonstrate and identify potential reproductive health and physical performance factors associated with lower body RSI in female service member.