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SYDNEY - A little bit of exercise will shrink the waistlines of the couch-bound far quicker than it will benefit active people, research proves.
A study by Murdoch Children's Research Institute and the International Diabetes Institute found that a sedentary person who walks just 2000 steps a day could significantly shed weight just by adding another 2000 steps.
Men would lose 2.8cm off the waist while women would lose 2.2cm.
But active people walking the recommended 10,000 steps a day would only reduce their waist circumference by 0.7cm if they added a further 2000 steps.
The study of more than 1100 Tasmanians, published in the International Journal of Obesity, is the first to prove definitively, using step pedometers, the impact exercise has on obesity, even when it is simply walking.
A person who is doing no exercise or not very much will get huge benefits from that little bit more, says Dr David Dunstan, manager of physical activity research at the International Diabetes Institute and one of the study's authors.
"In terms of obesity levels, we've proved there are huge benefits to be gained from this low starting point and that should be very encouraging for people," he said. "Of course, there are some benefits for those that are already doing more but the magnitude is just not the same."
The research, an offshoot of the national diabetes study AusDiab, tracked 1126 men and women who wore a pedometer on two weekdays and filled out a survey about their physical activity, diet and television viewing.
On average, females walked slightly more steps than males.
- AAP