Calf pain at night is common in the following situations: First, consider calf gastrocnemius strain, such as after a lot of sports during the day, which often leads to a large amount of lactic acid accumulation at the calf gastrocnemius, resulting in soreness and pain, especially at night there will be spasmodic pain in the calf muscles. Secondly, consider that it is caused by calcium deficiency, calcium ions can inhibit the excitability of the neuromuscular junction. When calcium deficiency increases the excitability of the neuromuscular junction, it often leads to calf cramps and spasmodic pain in the calf, which can be manifested as hand and foot twitching in children. When such a condition occurs, early blood calcium testing must be performed. If it is clear that there is a decrease in blood calcium, calcium gluconate injections and calcium carbonate and high calcium foods are required for calcium supplementation if necessary.