The symptoms of short hamstrings may be caused by excessive exercise, or by myofasciitis, lumbar disc herniation, or pyriformis syndrome, etc. The symptoms of short hamstrings may be caused by excessive exercise, or by excessive exercise. 1. Excessive exercise: Excessive exercise of the lower limbs causes lactic acid to accumulate within the muscles, resulting in symptoms of leg pain and short hamstrings, which can be relieved after resting. 2. Myofasciitis: after the local muscle tissue gets cold, it will cause local blood vessel contraction and muscle spasm, which will easily lead to aseptic inflammation of leg muscles and fascia, causing thigh pain and short tendons. 3. Lumbar disc herniation: after the structure of lumbar disc undergoes degenerative changes such as hyperplasia and exudation, it will squeeze the surrounding sciatic nerve, which causes leg pain and shortness of tendon due to the stimulation of the nerve being squeezed. 4. Piriformis syndrome: the sciatic nerve runs along the piriformis muscle, and if the buttocks are affected by external impact or cold and other factors, it will lead to compression of the sciatic nerve and piriformis syndrome, which will cause pain in the legs and hamstrings, and other uncomfortable symptoms. There are many other causes of leg pain, short hamstring symptoms, such as trauma, lower extremity vascular disease, etc., if not relieved after rest, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, and comply with the doctor’s instructions for targeted treatment, so as to avoid delays in the condition.