It is more important to supplement carbohydrates at the beginning of preparation. Eat something 30 minutes in advance, and you will feel more energetic when you exercise. Stretching before exercise aims at reducing the viscosity of muscles, increasing the blood flow of exercise muscles, improving sports performance and reducing sports injuries. When you start fitness, you should practice strength primary fitness: when you do strength training, you should give priority to equipment training, supplemented by free weight, and give priority to stretching. The method is static stretching, not jumping up and down. Each part can be repeated 2 ~ 3 times, each lasting 15 ~ 30 seconds. In addition, in the process of equipment training, the target muscles should also be stretched between groups, and bodybuilders should pay attention to persistence and exercise methods.