There are many causes of thigh muscle pain, specifically the following: 1, thigh muscle pain: the most common cause is thigh muscle strain, activity is relatively large crowds, such as athletes, appear when strenuous activity. In muscle fatigue, due to insufficient muscle strength can also lead to muscle strain, which causes thigh muscle pain. 2, muscle chronic aseptic inflammation: common for myofasciitis recurring, aggravated by activity, reduced after rest, hot compresses can improve. 3, lumbar spine disease: common for lumbar disc herniation compression nerve, will lead to muscle pain on the back side of the thigh, aggravated when bending. 4, cold stimulation: when the muscle cold, due to poor blood circulation, causing local inflammation, will also lead to pain. 5, muscle fatigue: occurs after a large number of activities in a short period of time, the muscle for soreness and pain, most of which can recover by themselves.