What I do know is that using something physical for the purposes of inflicting pain carries too much risk that it will work too well, and the coach will be the one punished in the end.

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Physical pain warns us not to do something, walk on a broken ankle for instance.

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As the author, Professor Bernard Stewart, an internationally-noted expert in cancer causation, points out, there is a remarkable scientific consensus on the causes of avoidable cancer, and they relate to lifestyle choices that people can actually do something about: smoking, poor diet, excessive drinking, obesity, physical inactivity, and exposure to the sun.

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