Improving Movement Quality of Military Personnel to Protect Hips and Lower Limbs from Injury

Musculoskeletal injury (MSKI) contributes significantly to recruit attrition during military training, where females are 1.7-times more likely to sustain a MSKI than males. The current research programme assessed movement control in military recruit cohorts to better understand the interactions between movement quality, sex and injury risk. Study-1 undertook secondary data analysis of pre-training health, fitness and movement quality of Royal Navy Phase-1 recruits (n=956), relative to prospective MSKI data i.e. injury site (location), onset (acute vs. over-use), severity and when in training (time), to generate an injury prediction model (Chapter 4). Functional Movement Screen (FMS) total score significantly contributed to the model but only accounted for 8.5% of the variation in the data. Moreover, there was no difference between the pre-training FMS scores for males (14.6±2.3) and females (14.4±2.4), despite females sustaining 1.7-times more MSKI. All further investigations adopted the Hip &Lower Limb Movement Screen (H&LLMS), as FMS lacked focus on the hip. Study-2 conducted a 3D motion capture investigation of movement quality of Army Phase-2 recruits (15 male, 15 female). Differences in H&LLMS score and kinematics were assessed under three load conditions: unloaded; loaded to 30% bodyweight; and standardised load (16 kg) (Chapter 6). Load interacted with H&LLMS scores for the “knee over toe” fault, and ankle dorsiflexion and pelvic tilt kinematics, but not with sex. Study-3 investigated the feasibility of delivering a 12-week neuromuscular control exercise intervention and its effect on movement control of a mixed-sex cohort of Phase-1 military recruits (n=127) (Chapter 7). Troops were randomly block-assigned to the intervention (INT; n=97) or control (CON; n=32) group. The INT group completed 35% of the planned weekly sessions and their movement quality improved by 7%; whilst the CON group worsened by 14% (ΔH&LLMS: CON +3.8±6; INT -2.2±7; P≤0.001). Thus, movement quality can be influenced through physical activity interventions. An interaction exists between body weight, load carriage and movement quality. Additionally, movement quality is both positively and negatively modifiable, which may influence injury risk. The present findings indicate a randomised controlled trial is warranted to determine whether neuromuscular training to improve movement quality will reduce injury risk