If you are young, it is normal to gain weight at the beginning of exercise, because at the beginning of exercise, especially during strenuous exercise, you consume not fat, but water and sugar in your body, which will cause muscle aches and increase muscle fibers. When muscles grow, you will definitely gain weight. Losing weight is a long-term process, and it is impossible to have obvious effects in a few days. Unless you take some diet pills, but those have side effects on your body, just excluding water from your body will definitely "lose weight", but it will rebound quickly. Stick to losing weight. After half a year, you will find yourself strong, energetic and in perfect shape.