The document discusses overtraining in athletes, which occurs when there are excessive training demands that decrease performance and mental health. Overtraining is usually caused by a lack of recovery time between training sessions and competitions. It can lead to both physical and mental symptoms in athletes. Physically, overtraining causes decreased abilities, increased fatigue, and injuries. Mentally, it results in disrupted sleep, irritability, lack of motivation and concentration issues. The document recommends allowing for adequate recovery between training sessions, ensuring training is varied, limiting the intensity and volume of increases in training, and being aware of overtraining symptoms to prevent injuries and burnout in young athletes.