Common signs of overtraining syndrome include persistent fatigue, decreased performance, and prolonged muscle soreness. Athletes may experience changes in mood, such as irritability or depression, and may find themselves experiencing sleep disturbances. Other symptoms might include increased resting heart rate, frequent injuries, and reduced immunity, resulting in more frequent illnesses. These signs indicate that the body is not recovering efficiently from training stress, emphasizing the need for rest and recovery strategies. Recognizing these symptoms early can help prevent further complications and ensure effective training adaptation.