The patient’s calves are sore and painful at night. In this case, we should consider the causes of overexertion and calcium deficiency, as follows: 1. Overexertion: It may be due to overexertion during the day, such as long-distance walking, weight-bearing activities, and excessive sports, which can cause a large amount of lactic acid to accumulate in the calf area, and in the quiet state at night, we will feel a significant soreness and pain in the calf. 2, calcium deficiency: calcium ions can inhibit the excitability of the neuromuscular junction, when calcium deficiency neuromuscular excitability will increase, so it can be manifested as spasmodic pain in the calf at night, and also can be manifested as crampy pain in the calf muscle at night.