Sore legs and stomach may be caused by physiological factors, chronic strain, acute injury, calcium deficiency and so on. 1. Physiological factors: standing for a long time or strenuous exercise, resulting in increased metabolic products of the leg and stomach muscles, will cause leg and stomach pain, usually mild pain, can be relieved on their own. 2. Chronic strain: such as prolonged exposure to cold, prolonged heavy physical labor, can make the leg and stomach parts of the muscle aseptic inflammation, stimulated by inflammatory substances, will cause leg and stomach pain. 3. Acute injury: muscle strain or external blow, resulting in damage to the soft tissues of the legs and stomach area, will cause soreness in the legs and stomach, may also be accompanied by redness, mild swelling and other symptoms. 4. Calcium deficiency: long time partiality and picky eating, resulting in a lack of calcium in the body, there may be sore legs and tummies, and at night there will be leg cramps. If the symptoms of leg and stomach pain persist, it is recommended to consult a doctor for examination and treatment to avoid aggravation of the disease.