Behind the thighs jumping is the back of the thigh muscles appeared autonomic spasm, the reason for the spasm, consider is due to excessive labor or long time strenuous exercise, the back of the thigh muscles did not get relaxation, rest caused. Do not worry after this situation, first of all, you can relax the muscles, to rest mainly, do not do strenuous exercise, local can be patted with the hand, you can also use massage, physical therapy to let the throbbing muscles get relaxed, gradually will recover, similar to the muscle cramps. If there is no obvious trigger for the throbbing and no strenuous exercise, you need to check the blood trace elements to see if there is a calcium deficiency, and if there is a calcium deficiency, you need to supplement calcium.