When it comes to exercise, many people seem to fall into two distinct camps: those who love a vigorous, sweat-soaked workout and those who view it as a form of torment.

With hopes of getting more people up and moving, scientists are looking at the body's biological and chemical processes for clues to understanding what's behind differing attitudes toward exercise. That could mean there are factors beyond motivation and discipline to explain why some people enjoy exercising and others don't.

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