The idea that happiness leads to a longer, healthier life is moving from folklore to fact. As evidence accumulates, scientists search for the ways that being a happy person causes better health. Now comes evidence that happy people are more likely to exercise - a behavior known to improve physical health.

It's a finding drawn from a study by a team of researchers including Lauren Smith, MS and John Ruiz, Ph.D. at the University of North Texas and Heidi Hamann, Ph.D. at the University of Texas Southwestern Medical Center.

The study involved 276 college students who completed questionnaires about their personality and exercise habits. After filling out questionnaires, students' use of the university's on-campus gym was monitored for nine months through student ID card swipes on entry turnstiles. Results indicate that happier individuals not only reported exercising more but also entered the gym more frequently over the nine month follow-up. The findings were presented in March at the American Psychosomatic Society meeting in San Antonio, Texas where they received a meritorious citation.

"We've known for some time that happy people report their behaviors in a more positive light but this is some of the first objective evidence that they also engage in more positive health behaviors," Smith said. Ruiz adds that "it appears happy people not only engage in fewer health-damaging behaviors like smoking, but they are also more likely to engage in health-promoting behaviors." Such findings may help explain why positive people experience better health than people who are simply not negative.