EFFECTS OF A PROLONGED ACADEMIC BREAK ON BONE HEALTH AND PERFORMANCE VARIABLES AMONG COLLEGE ROTC CADETS

EFFECTS OF A PROLONGED ACADEMIC BREAK ON BONE HEALTH AND PERFORMANCE VARIABLES AMONG COLLEGE ROTC CADETS Allen L. Redinger1 & Breanne S. Baker1 1Oklahoma State University, Stillwater, Oklahoma PURPOSE: College ROTC members are training to become future military officers, who have a high prevalence of skeletal injuries. Unlike currently enlisted military, ROTC members have prolonged periods of inactivity during academic breaks that may alter bone health. This study evaluated the influence of a four-week winter break on bone density, biomarkers, body composition, and physical performance in ROTC and matched controls. METHODS: All participants were tested before and after winter break (Dec and Jan). ROTC cadets (n=18, age=20.4±2.4, BMI=24.0±2.1) engaged in an eight-week military training intervention prior to break while matched controls (n=18, age=21.2±1.8, BMI=24.0±2.4) were physically active at least 3x/wk before break. General health questionnaires, bone scans (DXA), serum parathyroid hormone (PTH) and sclerostin concentrations, and physical performance (1RM bench/leg press and VO2 max) were tested pre/post. A repeated measures ANOVA was used to test for group x time interactions and group or time effects, significance was set at p≤0.05. RESULTS: At baseline, groups were equivalent for all measures and no significant interactions or group effects were found. Sclerostin increased while total hip bone density decreased (Figure 1) but PTH and other bone measures remained unchanged. Both relative VO2 and leg press 1RM increased (both p≤0.040), despite no changes in training volumes or 1RM bench press. CONCLUSION: Both groups maintained exercise volumes and improved muscle strength and VO2 but sclerostin and hip bone density changes suggest bone resorption. These discordant results suggest both ROTC and Controls may have increased site-specific bone resorption which could be due to altered training modalities. Since skeletal injuries are common in young military personnel, a more detailed investigation of exercise and diet habits during academic breaks may be warranted for ROTC members. ACKNOWLEDGEMENTS: The authors would like to thank all participants and Drs. Buchanan, Black, and Bembens