Does striving toward goals help to make an activity more interesting, whether it's swimming laps around the pool, doing math homework or working on an assembly line?

Or do goals actually spoil enjoyment of an activity?The answer partly depends on your personality, says a University of Rochester psychologist.

"Some people savor the challenge of striving to be at the top," says professor Andrew J. Elliot. "They love getting the best grade on the test, or beating a sales quota. Measuring themselves against others is energizing."

But for others, having their performance compared with others triggers anxiety, he notes, adding: "They do better striving for personal bests."