Leg cramps in children, caused by calcium deficiency and muscle spasms caused by excessive exercise. 1, calcium deficiency: in addition to leg cramps, it will also be accompanied by obvious night sweats, poor mental state, easy irritability, more serious cases will be accompanied by obvious symptoms such as chicken chest, rib exostosis, square cranium, etc., physical weakness, easy to lose hair, you need to go to the children’s health department to do a trace elements and blood vitamin d test, if there is an obvious calcium deficiency, you need to promptly supplement lactated calcium or liquid calcium, such as zinc gluconate Calcium or pediatric calcium carbonate granules, along with vitamin D more than 800 units per day to promote calcium absorption, continuous supplementation for 2 to 3 months, this symptom should be able to quickly alleviate, every night pay attention to the child hot compresses. 2, excessive exercise: for children who do not usually physical exercise, sudden strenuous activity, easily lead to muscle contraction, especially at night or after strenuous exercise, it is easy to form a continuous muscle cell discharge, accompanied by severe pain, muscle tension, the symptoms need to be promptly given massage and hot compresses to relieve the late will be accompanied by obvious soreness symptoms lasting 2 The symptoms will be accompanied by obvious soreness for 2 to 3 days, and the child should be able to be relieved quickly with daily hot compresses and massage.