ABSTRACT: Most reasons for exercise can be grouped into health-related ‘therapeutic’ and challenge-related ‘mastery’ categories. Since these motives are not independent of personal needs and expectations, their associated psychological profiles may vary. In this preliminary cross-sectional investigation, we tested the possible differences in life-satisfaction, optimism, pessimism, and perceived stress between therapeutic and mastery exercisers as well as a non-exercising control group. Individuals who exercised for mastery reasons reported superior mental health profile in three out of the four dependent measures while those who exercised for therapeutic reasons did not differ from the non-exercising control group in any of the measures. Further, a composite score of mental health profile, derived from the difference between the sums of positive and negative measures, revealed that mastery exercisers reported the most favorable profile. Their mental health profile emerged to be superior to non-exercisers, but it did not differ statistically significantly from the profile of the therapeutic exercisers. The latter two groups did not differ from each other on this composite measure. These preliminary findings suggest that two very general motives for exercise might be associated with different psychological profiles, which merits future research attention.