Anaerobic respiration takes place when you demand your muscles to do vigorous work. Normally, aerobic respiration takes place but when energy is needed immediately, anaerobic respiration takes place. During anaerobic respiration,the body produces lactic acid, which leads to the burning sensation. Your lungs deliver oxygen to the muscles much slower than the rate you need, since you're putting your muscles through an extensive exercise, and this leads to muscle fatigue.