The symptoms of calf cramps after waking up in the morning may exist for the following two reasons: 1, before the symptoms appear because of work fatigue or excessive exercise and other reasons to make the calf muscle tension, strain, injury, after resting muscle relaxation, but the injury is not healed, after waking up in the morning calf suddenly force may appear calf cramps symptoms. 2, life, living environment and sleep environment is cold, humid. If the calf muscles and fascia feel the external stimulation, the blood circulation of the calf muscles and fascia and other soft tissues becomes poor. When resting and sleeping, there are no obvious symptoms, but after waking up, the sudden activity and ischemia induce the muscle spasm of the calf and the phenomenon of cramps.