There are a lot of swimming precautions, stretching and preparatory warm-up activities before swimming, to have adequate stretching of the muscles and joints, to prevent the state of leg cramps due to low water temperature after going into the water, without adequate warm-up activities may not adapt to the water temperature will lead to muscle overexcitation resulting in convulsions to pay attention to. Before swimming to eat, but can not eat too much, swimming on the body’s caloric consumption is relatively large, fasting swimming, it will cause hypoglycemia may lead to fainting. In the late eating to be fully active, after the water temperature is not too cool, it is best to approach and human body temperature is about the same, in the process of swimming, the amount of exercise should be controlled within the scope of control. Too much exercise is not a good result for exercise.