Overtraining (overtraining syndrome, sports disease) is a pathological condition of desadaptation, which develops when the volume and intensity of an individual's physical and psychological activities exceeds chronically their recovery capacity. Overtraining can be accompanied by one or several of listed further symptoms: - persistent fatigue, - declining athletic performance, - reducing desire to train, - loss of motivation, - persistent muscle soreness, - increased incidence of injuries, - quick fatigue, - depression, - sleep disturbance, - bad temper, - petulance, - appetite deterioration, - increased susceptibility to upper respiratory tract infections. A number of difficulties exist with regard to the recognition and diagnosis of the overtraining syndrome. During long-term championships in playing sports or during qualifying rounds before World Championships and Olympic Games, professional sportsmen often try to hide the early symptoms of overtraining from coaching team and