Sleeping calf belly soreness may be caused by factors such as exertion, varicose veins of the lower extremities, and deep vein thrombosis of the lower extremities. 1. Exhaustion: With more activity before going to bed, lactic acid accumulates in large quantities in the muscles of the calves, which can lead to the symptoms of soreness and swelling in the calves. 2. Varicose veins of the lower limbs: the disease is related to factors such as defective venous valves and elevated abdominal pressure. Poor blood circulation in the early stage will lead to symptoms of soreness and swelling of the calves, and the aggravation of the disease in the later stage may lead to hyperpigmentation and ulcers. 3. Deep vein thrombosis of the lower limbs: this disease is related to the damage of the vein wall, slow blood flow and other factors, after the thrombosis of the vein plexus of the calf muscle, the blood and oxygen supply to the calf is insufficient, and there may be pain and soreness in the calf. There are many factors that lead to sleeping calf soreness, it is recommended to consult a doctor in time to identify the cause of the disease and then treat it.