The front of the thigh appears sore, this situation is mainly due to two reasons. 1, due to the front of the thigh quadriceps muscle intense contraction or continuous contraction, which will lead to local consumption of electrolytes, energy and nutrients is relatively large, easy to appear sore feeling, and due to strenuous exercise and strain, will lead to the formation of local inflammatory lesions, inflammatory metabolites will stimulate the peripheral nerves, also easy to appear sore feeling. 2, due to the front of the thighs of the quadriceps muscle continued to be in a state of fatigue, such as sedentary, squatting, sitting, especially to do some relatively short bench, so that the quadriceps muscle continued to be in a state of tension, or sleep at night, the front of the thighs of the quadriceps muscle is not fully relaxed, and the night has a cold, will lead to local The formation of inflammatory lesions, inflammatory metabolites will stimulate blood vessels, resulting in a decrease in arterial blood supply, so that energy, nutrients, electrolyte function is reduced, and then the feeling of acidity will easily appear. In addition, persistent fatigue can lead to the formation of inflammatory metabolites, which can stimulate peripheral nerves and cause painful sensations.