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Overtraining is a physical, behavioral, and emotional condition that occurs when the volume and intensity of an individual's exercise exceeds their recovery capacity. They cease making progress, and can even begin to lose strength and fitness. Overtraining is a common problem in weight training, but it can also be experienced by runners and other athletes. Split training can help with overtraining.
Like pharmacological drugs, physical exercise may be chemically addictive. One theory is that this addiction is due to natural endorphins and dopamine generated and regulated by the exercise. Whether strictly due to this chemical by-product or not, some people can be said to become addicted to or fixated on psychological/physical effects of physical exercise and fitness. This may lead to overexercise, resulting in the "overtraining" syndrome.
A number of possible mechanisms for overtraining have been proposed:
Listed below are some of the common effects and cited signs of overtraining. Not all of the following effects will occur. The presence of any of these symptoms does not imply that an individual is overtrained.
Overtraining can be used advantageously, as when a bodybuilder is purposely overtrained for a brief period of time to supercompensate during a regeneration phase. These are known as "shock micro-cycles" and were a key training technique used by Soviet athletes.
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