The Effect of Military Load Carriage on Postural Sway, Forward Trunk Lean, and Pelvic Girdle Motion

International Journal of Exercise Science 10(1): 25-36, 2017. Musculoskeletal injuries are a common occurrence in military service members. It is believed that the load carried by the service member impedes stability and alters back and pelvis kinematics, increasing their susceptibility to musculoskeletal injuries, specifically in the lower extremities. The purpose of this study was to examine the effects of two different loads on postural sway, forward trunk lean, and pelvic girdle motion in United States Army Cadets. Twenty male Army Reserve Officers’ Training Corps Cadets participated in this study. Each participant performed the Modified Clinical Testing of Sensory Interaction (mCTSIB) Protocol and the Unilateral Stance (ULS) Protocol under three different rucksack load conditions (unloaded, 16.0 kg, and 20.5 kg loads). Mean postural sway velocity was recorded along with 2-D kinematics of the trunk in the sagittal plane and the pelvis in the frontal and sagittal planes. External loads of 16.0 kg (p \u3c 0.001) and 20.5 kg (p ≤ 0.003) significantly increased mean sway velocity by 16% to 52% depending on stance and visual condition, but did not produce significant changes in trunk and pelvic kinematics

The Influence of Body Armor on Balance and Movement Quality

International Journal of Exercise Science 11(1): 648-656, 2018. Body armor is essential to the protection of military personnel; however, body armor may impede the users balance and movement quality. A better understanding of the influence of body armor on balance and movement quality may help in the development of new guidelines for training standards and procedures to mitigate the risk of injury associated with wearing of body armor in warfighters. The purpose of this study was to identify the effects of body armor (combat boots, tactical vest and combat helmet) on balance and movement quality in male military cadets and personnel. Twelve male participants completed the Functional Movement Screen (FMS) and Star Excursion Balance Test (SEBT) under two separate conditions, body armor and non-body armor. Results indicated a significant difference in FMS composite score between the non-body armor and body armor conditions (p =.012), with the non-body armor condition resulting in significantly higher FMS scores than the body armor condition. Additionally, the FMS item score for shoulder mobility was significantly higher (2.25±0.62) in the non-body armor condition than the body armor condition (p= 0.03). The SEBT composite and the three individual reach distances were not significantly different between conditions. Based on the current findings, body armor within a 4.8 kg – 5.3 kg range does appear to impact movement quality as evaluated using the FMS in male military personnel and cadets. More research is needed to determine a threshold of compensatory movement patterns relative to an increase in body armor weight