<Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (June 2009) (Learn how and when to remove this template message) </Td> </Tr> <P> In sports science theory, supercompensation is the post training period during which the trained function / parameter has a higher performance capacity than it did prior to the training period . </P> <P> The fitness level of a human body in training can be broken down into four periods: initial fitness, parietal fitness training, recovery, and supercompensation . During the initial fitness period, the target of the training has a base level of fitness (shown by the first time sector in the graph). Upon entering the training period, the target's level of fitness decreases (shown by the second time sector in the graph). After training, the body enters the recovery period during which level of fitness increases up to the initial fitness level (shown by the third time sector in the graph). Because the human body is an adjustable organism, it will feel the need to adjust itself to a higher level of fitness in anticipation of the next training session . Accordingly, the increase in fitness following a training session does not stop at the initial fitness level . Instead the body enters a period of supercompensation during which fitness surpasses the initial fitness level (shown by the fourth time sector in the graph). If there are no further workouts, this fitness level will slowly decline back towards the initial fitness level (shown by the last time sector in the graph). First put forth by Russian scientist Nikolai N. Yakovlev (1911--1992) in 1949 - 1959, this theory is a basic principle of athletic training . </P> <P> If the next workout takes place during the recovery period, overtraining may occur . If the next workout takes place during the supercompensation period, the body will advance to a higher level of fitness . If the next workout takes place after the supercompensation period, the body will remain at the base level . </P>

In the supercompensation theory a decline in strength occurs in what phase
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