The Effect of Army Reserve Officer Training Corps Physical Training on Aerobic Fitness, Muscular Endurance and Body Composition

Abstract

Context: Soldiers actively participating in the Army must meet and maintain the Army’s body composition standards. Soldiers exceeding the weight standards require further assessment of body composition through gender specific body circumference measurements and must enroll in the Army body composition program if standards are not met. It is not clear the extent to which the Army’s current method for determining body composition compares with more widely accepted methods. Objective: To compare the Army’s current body circumference based method of assessing body composition to validated clinical assessments of body composition including skinfold thickness measurements and body circumferences and breadths. Design: Test-retest Setting: Human Performance Lab. Patients or Other Participants: 28 male (24.57±4.39 years) and 12 female (24.17±4.95 years) Army ROTC cadets from the University’s Warrior Battalion. Interventions: Body fat percentage (%BF) was calculated utilizing three separate techniques: 1) from body density as obtained using the Army’s current circumference measurement protocol (ARMY) for males (neck and umbilicus) and females (neck, waist and hip), 2) indirectly from lean body weight as determined via breadth, limb, and body circumference measurements (LBC) for males (waist circumference, knee circumference, and bi- iliac breadth) and females (umbilicus circumference), and 3) from body density calculated from skinfold thickness (SKF), measured with Lange calipers (Cambridge Scientific Industries, Inc., Cambridge, Maryland, USA) at three sites on the right side of the body, (triceps, supra-ilium, and thigh for females; chest, abdomen, and thigh for males). Percent body fat was calculated from body density using the Brozek 2-Compartment model equation. Main Outcome Measurements: A repeated measures ANOVA with an alpha level of p<0.05 was used to assess differences in %BF as calculated by LBC, SKF, and ARMY. Results: Body fat percentage in males as calculated via ARMY (16.79±4.00%) was significantly higher than LBC (11.86±3.19%, p<0.001) and SKF (12.25±3.14%, p<0.001). In females, ARMY (27.17±4.04%) was significantly lower than LBC (28.42±3.40%, p=0.001) and significantly higher than SKF (24.62±2.68%, p=0.026). Conclusions: Results from the current study indicate %BF determined using the Army’s current body circumference based measurements is inconsistent with more commonly accepted, validated methods such as skinfold thickness measurements. The overestimation of %BF for both genders brings into question the reliability of the Army’s current protocol. Future research should validate the existing Army protocol with a current “gold standard” of body composition such as the 4-Compartment model.