The Psychological and Physiological Consequences of Low Energy Availability in a Male Combat Sport Athlete.

PURPOSE To evaluate the effects of low energy availability (EA) on health and performance indices associated with the Male Athlete Triad and Relative Energy Deficiency in Sports (RED-S) models. METHODS Over an 8 week period, a male combat sport athlete adhered to a phased body mass (BM) loss plan consisting of 7 weeks energy intake (EI) equating to resting metabolic rate (RMR) (1700 kcal·day) (Phase 1), 5 days of reduced EI (1200-300 kcal·day) prior to weigh-in (Phase 2) and one week of ad libitum EI post-competition (Phase 3). EA fluctuated day by day due to variations in exercise energy expenditure. Regular assessments of body composition, RMR, cardiac function, cardiorespiratory capacity, strength & power, psychological state and blood clinical chemistry for endocrine, bone turnover, hydration, electrolyte, renal, liver and lipid profiles were performed. RESULTS BM was reduced over the 8 week period by 13.5% (72.5 to 62.7 kg). No consequences of Male Athlete Triad or RED-S were evident during phase 1, where mean daily EA equated to 20 kcal·kg·FFM·day (range: 7 to 31 kcal·kg·FFM·day) and BM and fat mass (FM) losses were 6.5 and 4.4 kg, respectively. However, consequences did present in phase 2 when mean daily EA was consistently <10 kcal·kg·FFM·day, as evidenced by alterations to endocrine hormones (e.g. testosterone: <5 nmol.L) and reduced RMR (-257 kcal·day). CONCLUSION Data demonstrate that 7 weeks of daily fluctuations in EA equating to a mean value of 20 kcal·kg·FFM·day permits reductions of BM and FM without perturbations to physiological systems associated with the Male Athlete Triad and RED-S. In contrast, a subsequent period of 5 consecutive days of EA <10 kcal·kg·FFM·day induced consequences of Male Athlete Triad and RED-S.