October 8, 2009 (EurekAlert) - Attention weekend warriors: the simple act of exercise and not fitness itself can convince you that you look better, a new University of Florida study finds.People who don't achieve workout milestones such as losing fat, gaining strength or boosting cardiovascular fitness feel just as good about their bodies as their more athletic counterparts, said Heather Hausenblas, a UF exercise psychologist. Her study is published in the September issue of the Journal of Health Psychology.

"You would think that if you become more fit that you would experience greater improvements in terms of body image, but that's not what we found," she said. "It may be that the requirements to receive the psychological benefits of exercise, including those relating to body image, differ substantially from the physical benefits."

The study by Hausenblas and graduate student Anna Campbell is the first to systematically analyze the wide-ranging effects of exercise on body image by examining all intervention studies on the subject until June 2008. From the 57 publications, the researchers found conclusively that exercise buffed up the way people see their bodies regardless of the actual benefits, but the results varied.

Negative body image has grown to almost epidemic proportions in the past 20 years, with as many as 60 percent of adults in national studies saying they don't like the way their bodies look, Hausenblas said.

Americans spend billions of dollars a year for products designed to change their body size and shape, including diet pills and various cosmetic procedures, she said.

"Body dissatisfaction is a huge problem in our society and is related to all sorts of negative behavior including yo-yo dieting, smoking, taking steroids and undergoing cosmetic surgery," she said. "It affects men and women and all ages, starting with kids who are as young as five years old saying they don't like how their bodies look."

The psychological advantages of exercise have been less explored, including the reduction of depression or confidence in body image, compared with the well-researched and understood physical benefits, she said.

The study found no difference in body image improvement between people who met the American College of Sports Medicine guidelines by exercising at least 30 minutes a day five days a week and those who did not, Hausenblas said. The guidelines are considered the minimum amount of exercise needed to receive the health related benefits of physical activity, she said.

"We would have thought that people exercising this amount would have felt better about their bodies than those who did not work out as much," she said.

In other results, the study showed slightly larger benefits from exercise in terms of improving body image for women than men, Hausenblas said.

"We believed the gap would be much bigger, but what could be coming into play is the rise of body image issues among men," she said. "We're seeing more media portrayals of the ideal physique for men rather than the overriding emphasis on women we did in the past."

Age presented another difference, with older people most likely to report enhanced body images from exercise, Hausenblas said. The gap may be explained by the older generation having more concerns about their body image than young people, who tend to exercise more, she said.

While the frequency of exercise mattered for boosting body perceptions, there were no differences for the duration, intensity, length or type of exercise, the study found.

"People who say they have high body dissatisfaction tend to exercise the least, so we wanted to take it a step further and see whether exercise causes people's body image to improve," she said.

Kathleen Martin Ginis, a kinesiology professor at McMaster University in Ontario, Canada, and exercise expert, praised the research. "This is an important study because it shows that doing virtually any type of exercise, on a regular basis, can help people feel better about their bodies," she said. "With such a large segment of the population dissatisfied with their physiques, it's encouraging to know that even short, frequent bouts of lower intensity exercise can improve body image."