If you're beginning a new workout regimen, don't expect too much of yourself--or too little. Results of a study by researchers at Duke University Medical Center suggest that, left to their own devices, people gravitate to a moderate exercise program that's neither too lax nor too ambitious--the equivalent of briskly walking 11 miles each week. The investigators surmise that smaller doses of high intensity exercise may enable people to better stick to their exercise program.
Led by William Kraus, Ph.D., researchers studied 87 "couch-potatoes" who were randomly "prescribed" one of three 9-month supervised exercise programs. A low exercise group worked out an average of 187 minutes per week at about 50 percent of peak intensity; a moderate group, 123 minutes at 65-80 percent intensity; and a high group, 180 minutes at 65-80 percent intensity.
After the supervised period, subjects were observed for an additional six months during which they were free to work out or not. On average, the high exercise group reduced both the time spent per week and the intensity of their workouts. The low exercise group also decreased the number of minutes per week they exercised, but 68 percent significantly increased their workout intensity. The exercise patterns of the moderate group proved to be the most sustainable.