Abstract: Why the body's sport ability can be improved through exercise?This is a question that people have been trying to answer for a long time and it is also the focus and hotspot of sports science research since sports scientific training. " Supercompensation" and " adaptation" are two classic theory of the world in the field of sport training explaining human exercise ability changes in training.In 1930 s, researchers began to focus on energy metabolism of human activity.In 1960 s, the supercompensation's phenomenon of muscle glycogen reserves was found in exhaustive exercise.In 1970 s, Yakovlev extend muscle glycogen super-compensation to the area of the athletic training and super-compensation theory for sports training was proposed.Under the influence of the theory of “Stress Adaptation”by Selye in 1950 s, “Adaptation”has become an important basic theory in sports training since the 1960 s.After this, a series of doctrine and theory to attempt to reveal the relations between athletic ability growth and sports training and to predict and assess changes in exercise capacity, such as the " Fitness-Fatigue Model", the " Functional Reserves Model", the " Change-Adaptation Time Dynamic Model" and the“Performance Potential Metamodel”have appeared.However, given the complexity in composition and development of athletic ability and limitations in current human understanding of their own, so far a variety of models have not been able to achieve these objectives, and also require more in-depth to study.