It is all a question of intensity. If I have a leisurely stroll around the park, spending an hour on the 2-mile loop looking at leaves and the lake, I will have brought peace to my soul but not burned enough calories to justify eating a pint of ice cream. If I had run a few laps around the same park during that hour, I might have missed a few of the trees but would have earned the right to relish the ice cream.
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