There are many reasons for weight gain after exercising for a period of time. It may be due to the improvement of muscle mass after exercise, uncontrolled diet, insufficient intensity of exercise, etc. Measures can be taken according to the reasons. 1. Because the proportion of muscle is greater than that of fat, if there is a decrease in body fat and an increase in muscle, this may also manifest as weight gain. Muscle can increase limb strength and improve metabolism, which is relatively good and generally does not need to be toned. 2. Exercise intensity or frequency is not enough, it is recommended that at least 150 minutes of moderate-intensity aerobic exercise per week, long-term adherence, in order to ultimately achieve the purpose of weight loss. 3. Appetite increases after exercise, the amount of food is more than usual, more than the energy consumed by exercise, resulting in weight gain, it is recommended to reasonably control the amount of food. If the weight gain after exercise is obvious, it is recommended to consult a doctor.