Running thigh root and crotch joint pain, may be related to physiological factors or pathological factors, such as lactic acid accumulation, muscle strain, hip joint injury, etc.. 1. Physiological factors: running before other sports, resulting in the accumulation of local lactic acid, will cause running thigh root and crotch joint muscle pain. After resting for a while, it can usually be relieved by itself. Avoid high-intensity exercise during this period, so there is no need to worry too much. 2. Pathological factors (1) Muscle strain: If the amplitude is too large or the running intensity is too high during running, it may lead to local muscle strain and pain at the thigh root and hip joint. (2) Hip joint injury: such as hip synovitis, may be due to long-term running on the hip joint caused by the cumulative damage, the symptoms may be mild only manifested in the thigh root and hip joint pain, the symptoms are more serious when the activities of the obstacles, such as limping, walking difficulties, and so on. Running thigh root and crotch joint pain there are other reasons, such as trauma, iliotibial bundle tension, etc., if the rest does not relieve, it is recommended to consult a doctor in time for further examination, in the doctor’s comprehensive analysis of the cause of the disease, and comply with the doctor’s instructions to choose a reasonable treatment plan.