Association Between Musculoskeletal Injuries and the Canadian Armed Forces Physical Employment Standard Proxy in Canadian Military Recruits

Abstract

Introduction Musculoskeletal injuries (MSKIs) and recruitment are major challenges faced by modern military forces. The Canadian Armed Forces uses a physical employment standard (PES) proxy to determine occupational fitness and job suitability. It is unknown whether the performance on the PES proxy can be also used as predictor of MSKIs. The purpose of this study was to investigate for relationships between age, sex, body composition, aerobic fitness, performance on the Canadian Armed Forces PES proxy (FORCE evaluation), and risk of sustaining a MSKI requiring intervention in the Training Rehabilitation Program (MSKI-TRP1) during Canadian Basic Military Qualification. Materials and Methods This was a retrospective analysis of MSKIs in recruits introduced in the Training Rehabilitation Program (TRP1) in 2016 and 2017. A two-tailed t-test and a multivariate stepwise logistic regression were completed to investigate the interrelationships of sex, age, FORCE performance (20 m rushes, sandbag lift, intermittent loaded shuttles, sandbag drag) and health-related characteristics (waist circumference, predicted peak oxygen consumption [$\dot{V}$O2peak]), and odds for sustaining a MSKI-TRP. Results The MSKI-TRP1 intervention rate observed was 4.3%. Rehabilitation duration was an average (SD) of 87 (76) days; nearly 80% of MSKI-TRP were lower body injuries. MSKI-TRP recruits were older, had a lower score on FORCE, and had a larger mean waist circumference and lower $\dot{V}$O2peak than non-TRP1 recruits (all P < 0.01). Recruits with performance lower than 1 SD below mean on the 20 m rushes, intermittent loaded shuttle, or sandbag drag were 2.69 (1.89–3.83), 2.74 (1.91–3.95), and 2.26 (1.52–3.37) times more likely to sustain a MSKI-TRP1, respectively (all P < 0.01). Recruits with $\dot{V}$O2peak lower than 1 SD below mean were also 2.19 (1.30–3.70) times more likely to sustain a MSKI-TRP. Neither sex, age, nor waist circumference impacted the risk of MSKI-TRP1 when controlling for FORCE performance. Conclusions The Canadian Armed Forces PES proxy performance can be used to assess the odds of sustaining a MSKI-TRP1 in Canadian military recruit training.

Factors Predicting Training Delays and Attrition of Recruits during Basic Military Training

“…Lower pre-BMT levels of muscular strength and endurance [ 17 , 21 ] and cardiorespiratory fitness [ 8 , 17 , 20 ], have been associated with a greater risk of injury in recruits. In support of this previous research, the current investigation similarly found that lower baseline cardiorespiratory fitness and muscular fitness were associated with a higher risk of injury during BMT.…”

“…Several risk factors have been consistently identified that predict premature attrition and injury during BMT, with these factors often overlapping across both adverse outcomes. These include sustaining a musculoskeletal injury during training [ 12 , 13 , 14 ], injury history prior to military training [ 15 , 16 , 17 , 18 , 19 ], lower levels of muscular strength and endurance [ 8 , 12 , 13 , 17 , 19 , 20 , 21 ], and demographic factors such as older age [ 19 , 22 ], female sex [ 13 , 18 , 22 ], lower education level [ 12 , 15 ], and smoking status [ 13 , 14 ]. However, these risk factors are typically only measured once, at recruit entry to BMT.…”

Efecto del curso avanzado de combate sobre cualidades físicas condicionantes y características antropométricas en alumnos de la Escuela Militar de Cadetes General José María Córdova de Bogotá D.C. (Effect of the advanced combat course on conditioning phy

“…Debido a lo anterior, el acondicionamiento físico es el pilar fundamental que requiere un militar para poder desempeñar las labores propias de su profesión, para ello el entrenamiento básico y los cursos militares específicos, se tienen que caracterizar por brindar un mejoramiento significativo de las capacidades de la condición física incluyendo su composición corporal, la adaptación aeróbica y anaeróbica al ejercicio, la fuerza muscular del tren superior e inferior, la agilidad, la potencia y resistencia muscular (Chassé et al, 2020;Hazell et al, 2010;Hendrickson et al, 2010).…”

“…Con el mejoramiento de la composición corporal se logra un aumento en la efectividad para el cumplimiento de las tareas militares y con ello se alcanza una reducción del número de lesiones por el sobrepeso (Smith et al, 2012). La evaluación de variables como la circunferencia de cintura, así como de la predicción del consumo máximo de VO2, determinan información valiosa del progreso de los planes de entrenamiento en reducir el riesgo de enfermedades cardiovasculares y mejorar tanto los componentes del acondicionamiento y en definitiva del estado de salud del militar (Chassé et al, 2020). Por otro lado, el nivel de condición física y la determinación de la antropometría del individuo que se ve sometido a cargas de peso, son factores importantes para el tipo de actividad militar.…”

“…Además, los altos niveles de capacidad aeróbica como de fuerza muscular, sobre todo en el tren inferior del cuerpo, son requeridas para el desempeño tanto de un deportista como de un militar (Santtila et al, 2009). De esta manera, un buen acondicionamiento muscular y en general un adecuado desempeño físico son factores importantes en la prevención de eventos como las fracturas por stress y lesiones en miembros inferiores (Chassé et al, 2020). Incluso, la especificidad en la adaptación al entrenamiento de resistencia con altas cargas durante las fases iniciales del entrenamiento militar llevan a la adaptación neuromuscular y posteriormente a la hipertrofia del musculo (Wang et al, 2013).…”