Overtraining is a state of long-term decline in athletic ability, which is the result of long-term accumulation of many factors. We generally divide overtraining reactions into sympathetic and parasympathetic types.
Sympathetic nerve and parasympathetic nerve belong to the autonomic nervous system of human body, and these two nerves inhibit each other in function. The main function of sympathetic nerve is to make the human body enter a "state of stress consumption", increase the heart rate and blood pressure, and promote the human body to enter catabolism, while parasympathetic nerve makes the human body enter a "state of resting recovery", reduce the heart rate and blood pressure, and promote the synthetic metabolism of the human body.
During training, especially during high-intensity training, sympathetic nerves are excited and parasympathetic nerves are inhibited. After the training, the parasympathetic nerve is gradually excited, and the sympathetic nerve is gradually inhibited, and the two are changing to maintain the balance of the body.
According to the research, generally speaking, the overtraining performance of athletes in strength and explosive events is "sympathetic", showing physical fatigue, but high spirits and poor sleep quality are often caused by excessive training intensity and long duration. The performance of endurance athletes' overtraining is mostly "parasympathetic", which is manifested as physical fatigue, listlessness and lethargy, which is often caused by overtraining.