Hello, you can't gain muscle and lose fat at the same time. Aerobic training will definitely consume a small part of muscle tissue, so it is recommended that you do aerobic training no more than twice a week for 40~80 minutes each time, and at the same time, with sit-ups, you can quickly lose abdominal fat. Secondly, you must train enough equipment, which is the only way to reduce muscle consumption, but the effect of increasing muscle is not obvious. You must also get enough protein after breakfast and training.