The muscle cramps are caused by the following: 1. calcium deficiency, in the case of hypocalcemia, muscle excitability is increased, and muscle tonic spasms can occur with light activity, especially during sleep. 2. peripheral neuropathy leads to abnormal discharge, causing muscle tonic spasms, clinically the most common is the ankle tube syndrome, mainly due to nerve compression and abnormal discharge. The most common clinical condition is the ankle tube syndrome, which is caused by abnormal discharge of nerves due to compression, and can be effectively improved by early closure therapy. 3. Muscle strain, especially after a lot of activities, and the daily activity is relatively large, the muscle is in a state of long-term strain, which can easily induce muscle spasm and lead to tonic contraction. Therefore, further examination of the cause of the cramp is needed and treatment will only be effective if the cause is addressed.