SAT-LB4 Novel Hormonal and Metabolic Markers of Recovery From Overtraining Syndrome Unveiled by the Longitudinal ARM of the Eros Study - the Eros-Longitudinal Study

Background: Overtraining Syndrome (OTS) is an unexplained underperformance syndrome triggered by excessive training, insufficient caloric intake, inadequate sleep, and excessive cognitive and social demands. Investigations of markers of the challenging recovery from OTS have not been reported to date. The objective of the present study is to describe novel markers, and biochemical and clinical behaviors during the restoration process of OTS.Design: A 12-week interventional protocol in 12 athletes affected by OTS was conducted, including increased food intake, transitory interruption of the trainings, improvement of sleep quality, and management of stress.Methods: We assessed 50 parameters, including hormonal responses to an insulin tolerance test (ITT), basal hormonal and non-hormonal biochemical markers, body metabolism and composition. Results: In response to an ITT, early cortisol (p = 0.026), early GH (p = 0.004), and late GH (p = 0.037) improved significantly. Basal estradiol (p = 0.0002) and nocturnal urinary catecholamines, (p = 0.043) reduced, while testosterone (p = 0.014), testosterone:estradiol (T:E) ratio (p = 0.0005), freeT3 (p = 0.043), IGF-1 (p = 0.003), and cortisol awakening response (CAR) (p = 0.001) increased significantly. All basal parameters and early responses to ITT normalized, when compared to healthy athletes. Basal metabolic rate, fat oxidation, body fat, muscle mass, and hydration status had partial but non-significant improvements. Conclusion: After 12 weeks, athletes affected by actual OTS demonstrated substantial improvements, remarkably IGF-1, freeT3, CAR, testosterone, estradiol testosterone:estradiol ratio, CK and catecholamines, and early cortisol, early prolactin, and overall GH responses to stimulations.