It is possible to have sore thigh muscles for the following reasons: 1, the most common reason is prolonged walking, excessive labor or a lot of exercise, may lead to a large number of harmful metabolites in the thigh, stimulating the muscle, fascia and other soft tissue acute inflammation, resulting in local soreness and swelling symptoms. Patients with fasciitis may only experience soreness and swelling in the legs at first, and only with the aggravation of the symptoms will the pain appear and the pain increase with sudden activity. The actual leg activity can be a good way to relieve the symptoms, and rest can aggravate the painful symptoms. 3, patients with lumbar disc bulge may also have the feeling of soreness and discomfort in the thighs, the degree of nerve compression in patients with disc bulge is relatively mild, so there may be only the symptoms of soreness and discomfort in the legs, but not the symptoms of numbness and pain in the legs.