Calf pain in the morning may be caused by over-exercise, calcium deficiency, lumbar disc herniation and other reasons. 1. Excessive exercise: excessive exercise the day before leads to more local lactic acid, lactic acid accumulation at night, lactic acid will stimulate the peripheral nerves around, causing pain, get up in the morning can feel calf pain. 2. Calcium deficiency: Calcium deficiency will lead to elevated neuromuscular excitability, which can lead to spasmodic contraction of calf muscles during sleep, causing muscle damage and calf pain in the morning. 3. Herniated lumbar disc: When a herniated lumbar disc compresses the sciatic nerve, it can cause radiating pain, i.e., pain in the thigh and calf. Calf pain in the morning may also have many reasons to exclude physiological reasons, should be timely to the hospital to improve the examination, clear cause of the disease in a timely manner to give targeted treatment.