1. The process of acquiring, developing, educating, establishing, learning, or training new responses in an individual. Used to describe both respondent and operant behavior; in both usages, refers to a change in the frequency or form of behavior as a result of the influence of the environment.
2. The application of a structured training program to prepare cardiovascular, muscular, and psychological readiness in human, canine, and equine athletes for competition or strenuous events.
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