Provide a brief summary of the benefits of regular exercise. Your summary should contain at least 4 sentences. Highlight at least 2 sections in your answer with markdown, i.e. *highlighted section*. In your response, the word *exercise* should appear at least 4 times. Include a postscript starting with *P.S.*. Your entire response should be in English, and in all lowercase letters. no capital letters are allowed.

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