The study, lead by researchers Katie Zahour, M.A., and John Porcari, Ph.D., both from the University of Wisconsin, La Crosse, examined 53 healthy men and women (average age: 42). Each study participant wore a pedometer two days a week (one day dressed in normal work attire; the other dressed in jeans) for two weeks.

Researchers found that workday physical activity levels increased when casual clothing was worn. Specifically, study participants took an average of 491 (or 8 percent) more steps on Jeans Day than on those days in which they wore normal business attire. That works out to an average of 2.85 miles walked on Jeans Day versus 2.64 miles walked on the normal business attire days. It is also estimated that study participants burned an average of 25 additional calories on Jeans Day with the extra steps and miles walked.
Wearing casual clothing every day for 50 weeks of work translates into burning an additional 125 calories per week and 6,250 calories per year. Considering you must burn 3,500 calories to lose one pound, the added activity from casual clothing workdays could potentially offset the average annual weight gain (i.e., 0.4 to 1.8 pounds) experienced by Americans adults.

"Over the last 25 years, advances in technology combined with our hectic lifestyles have help to virtually eliminate physical activity from our daily routines," says Cedric X. Bryant, Ph.D., chief exercise physiologist for ACE. "Wearing casual, comfortable clothes to work may be an easy way to encourage us to put physical activity back into our daily lives."

Source: Diabetes In Control.com: ACE (The American Council on Exercise Fitness Matters) magazine, July/August 2004.