Hi, Welcome to Healthcaremagic.com. I had gone through your question I can understand your concern about muscle spasm. There are many causes about muscle spasm but for prolonged period as you mentioned is mostly because of calcium deficiency or respiratory alkilosis. For both the cases you need to take calcium supplements and check if you have heavy breathing. Most of the times it happens because of sudden sharp movements which needs fast muscle contraction. You must keep your leg slightly in Bend position and don t stretch your legs with too much force. In case you feel persistent pain and tenderness you can also take skeletal muscle relaxants like Thiochochicene. Hope my answer will help you. Regards Dr Muzaffer