"For people who've been really sedentary, you're getting a benefit almost immediately. Just get off the couch," advised the study's lead author, Dr. Timothy Church, director of the Laboratory of Preventive Medicine Research at the Pennington Biomedical Research Center at Louisiana State University.
The findings are published in the May 16 issue of the Journal of the American Medical Association.
The researchers recruited 464 postmenopausal women who were considered overweight or obese. All of the women had some degree of high blood pressure, and none was exercising at all at the start of the study.
The women were randomly assigned to one of four groups: the control group that would remain sedentary; a light exercise group that averaged 72 minutes a week of exercise; a moderate exercise group that averaged about 136 minutes a week; and a high exercise group that completed nearly 192 minutes of exercise each week.
The researchers measured the women's peak oxygen consumption at the start of the study, and then again after six months of exercise. They found that the women in the light exercise group increased their peak oxygen consumption levels by 4.2 percent. The moderate exercise group saw a 6 percent rise, while the heavy exercise group upped their cardiorespiratory fitness by 8.2 percent.
"This is great news for couch potatoes and for the aging," said Church. "There are people that can't obtain the recommendations for exercise, but now, we see if you can't get 150 minutes a week, you stand to benefit even if you get half that."