Calf belly hardness may be excessive exercise, varicose veins of the lower extremities, lumbar disc herniation and other reasons. 1. Excessive exercise: If you exercise strenuously for a long time, it will lead to a large accumulation of lactic acid and muscle spasm at the calf belly, resulting in a hard calf belly, which may be accompanied by a feeling of acidity, pain, etc. You can reduce the intensity and duration of exercise, and stretch the calf muscles sufficiently after exercise. The situation can be avoided by reducing the intensity and duration of the exercise and stretching the muscles of the calf area sufficiently after the exercise. 2. Varicose veins of the lower limbs: Varicose veins of the lower limbs can lead to impaired blood circulation and obstruction of venous blood return, which can lead to the phenomenon of hardness in the calf stomach. It can be relieved by avoiding sitting and standing for a long time, and in serious cases, surgical treatment is needed. 3. Lumbar disc herniation: it can be manifested as lumbago, cauda equina syndrome and radiating pain in the lower limbs, etc., which may cause tightness in the calf tummy and hardness in the calf tummy. It can be relieved by more rest, local massage, etc. In serious cases, surgery is needed. Calf stomach hardness may also be caused by other reasons, frequent, long time can not be relieved, it is recommended to seek medical advice as soon as possible, improve the examination after targeted treatment.