It is not easy. Thin people gain weight and become strong easily. So, what about skinny? First of all, we must find out the health status. Some people suffer from nervous system diseases such as stomach, intestine, pancreas and kidney. With loss of appetite, even anorexia, nausea and vomiting at the sight of food. These people have to go to the doctor because of their thin feet. Everyone else is thin, but healthy and feels good. These people are thin, largely due to malnutrition or lack of exercise. Second, the diet is regular, not partial eclipse. Some people are so eager to get fat that they always like to eat snacks, but they don't want to eat anything when they eat, which affects their appetite. This is noteworthy. Foods rich in vitamins, inorganic salts, trace elements and pectin, such as fish, meat, dairy products, vegetables and fruits, should be selected under the guidance of doctors or nutritionists. Vegetables and fruits contain organic acids and essential oils, which help to increase appetite and stimulate iron secretion in gastrointestinal digestion. Third, we should strengthen physical exercise. Some people mistakenly think that sleeping more will make them fat, which is wrong. Sleeping more can only relax the muscles. Only by actively participating in sports activities, such as gymnastics, walking, skating, cycling and swimming, can we exercise, stimulate appetite and gain weight. Here I recommend a set of aerobics that is easy to learn. Exercise time should not be selected within three hours after meals. Exercise equipment needs a rubber rope, a gymnastics stick and a pair of dumbbells weighing 3- 15 kg.