Novel insights of overtraining syndrome discovered from the EROS study.

Our findings suggest that OTS is likely triggered by multiple factors, not restricted to excessive training, resulted from a chronic energy deprivation, leading to multiple losses in the conditioning processes typically observed in healthy athletes, as a combination of 'paradoxical deconditioning' processes, which explains the gradual and marked loss of physical conditioning found in OTS. We, therefore, suggest that the term 'paradoxical deconditioning syndrome' better represents the features of this syndrome.