Exercise is necessary for good health. First, exercise can stimulate nervous system because it controls all parts of a body. Second, exercise can reduce risk of having cancer. Third, exercise reduces the risk of heart disease. forth, exercise can help you fall asleep faster. Fifth, exercise helps you maintain a healthy weight. Sixth, exercise makes you happier. Seventh, exercise lowers high blood pressure. Eighth, exercise reduces the severity of asthma. Ninth, exercise reduces diabetic complications. Tenth , exercise improves oxygen and nutrient supply to all cells in your body. Eleventh, exercise allows you to improve muscle strength, joint structure and joint function. Twelfth, exercise promotes brain health. Last, people can be healthier by doing exercise. Exercise gives many can be benefits to people who do it.