The reasons why patients sleep with thigh cramps are mainly the following: 1, muscle strain and injury: strenuous sports during the daytime, or too many sports activities in a short period of time, can cause strain on the thigh muscles. A large amount of lactic acid will accumulate in the thigh muscles, so there will be spasmodic pain in the thigh, especially at night in a quiet environment spasmodic pain will be particularly obvious. 2, calcium deficiency: calcium ions can inhibit the excitability of the neuromuscular junction, the excitability of the neuromuscular junction increases when calcium deficiency, so it often causes leg cramps, and cramps are also more serious at night. This situation should be tested for blood calcium, and if it is clear that there is low blood calcium, it should be treated with active calcium supplementation.