Verheijen, who has also studied exercise physiology and sport psychology as well as taking a one-year Science in Football course, is not without his critics.

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But Winter, a professor of the physiology of exercise, says there are many factors in play when it comes to assessing player health.

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And the January 5, 1995 issue of the journal Physiology and Behavior reports that exercise decreases tension and boosts self-esteem.

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