Background: Body composition is an important determinant of athletic performance that is directly influenced by training and detraining. Collegiate athletes experience substantial variability in training intensity during a season, but little research has been conducted to track changes in body composition across periods of intense training and breaks from structured sport-related activities.
Methods: Body weight and composition (fat free mass and fat mass) were measured in members of a collegiate men's basketball team over the course of an 11-week summer training period. Dual X-ray Absorptiometry (DXA) scans were completed at the beginning of summer training (June 2019), at the end of the 7-week intense training period (July 2019), and after a 4-week break (late August 2019). For analysis measures were converted into indices (kg/m2).
Results: Fat free mass index increased (p < 0.01) and fat mass index decreased (p = 0.01) during the 7-week training period. Significant decreases in fat mass index (p = 0.02) were seen between June and August. Fat free mass index decreased from July to August (p < 0.01). No significant changes were seen in total body mass throughout the summer training period.
Conclusion: These data demonstrate cyclic changes in body composition during a summer training period that could impact athletic performance. Future research should further evaluate potential mediators and moderators of changes in body composition and include performance measures. Research in this capacity would allow trainers to optimize performance in athletes and bolster team performance.