When one exercises his fitness level increases accordingly. During the rest period your body gets the chance to recuperate and make itself stronger. Correct exercises only, leads your fitness level to improve at a faster rate rather than a fitness program that was not designed to meet your specific health and fitness requirements. When a beginner starts to exercise his fitness level tends to increase quite rapidly at first and gradually slow down as each new level of exercise fitness is reached. It is advised that when the fitness level tends to slow down, change your training program so that you get some additional rest rather than increasing your workout loads.