Consider physiological reasons, varicose veins of the lower limbs, venous thrombosis of the lower limbs, muscle strain and other reasons for calf soreness at night. 1. Physiological reasons: such as walking or standing too much during the day, the symptoms can be relieved by resting and elevating the lower limbs. 2. Varicose veins of the lower limbs: superficial vein dysfunction of the lower limbs will cause the lower limbs to show stripes or lumps of vascular tortuous expansion, accompanied by a feeling of swelling in the lower limbs. 3. Lower extremity venous thrombosis: prolonged bed rest or lower extremity trauma can easily cause lower extremity venous thrombosis, which will result in swelling of calves and aching sensation, and can be diagnosed clearly by lower extremity vascular ultrasound. 4. Muscle strain: if strenuous exercise or too much running and jumping can cause gastrocnemius muscle strain, calf soreness and swelling, through hot compresses, massage symptoms can be reduced. If the calf soreness at night does not improve through rest, it is best to go to the hospital for examination.