You, on the couch – listen up. Forget jogging. Don’t even break a sweat. Just get up and move.
Scientists at the Mayo Clinic have studied 20 self-described couch potatoes – half of them lean and the other half termed “mildly obese” – and found that the lean people are moving 21/2 hours a day more.
And that means they’re burning 350 calories a day more than their heavier counterparts.
This is the first study to show that daily activity, apart from actual exercise, is important in weight control, according to Dr. James Levine, the Mayo Clinic endocrinologist who led the study. “I couldn’t believe it,” he said. Results of the study will be published in today’s issue of the journal Science.
“This gets to the soul of America,” he said. “Most Americans are sedentary. This finding offers a beacon of hope. You don’t need the gym. There are other ways to stay lean.”
The researchers used the term NEAT – for “non-exercise activity thermogenesis” – to describe the movement being measured.
They advertised for couch potatoes, and 20 men and women volunteered. First, they were matched for age and activity level at work. Then, for 10 days, they wore undergarments embedded with sensors like those found on fighter-jet control panels. Every half-second, the sensors recorded posture and movement.
The volunteers ate three meals each day prepared especially for them at the hospital. Each morning, they exchanged yesterday’s underwear for a new set; researchers weighed each person and downloaded the data from yesterday’s sensors into a computer.
And they found that the lean people spent more time on their feet, moving.
In a second phase of the study, lean people were assigned to eat more and obese people to eat less, again for 10 days. Their movements were recorded and, no matter the weight gain or loss, NEAT levels remained the same for individuals. The lean group even fidgeted more than the other group, researchers said.
Levine said the findings led to the suspicion that “a person’s interest in moving around is biologically driven,” perhaps as a result of a neurological defect.
But he emphasized that people can alter their activity levels.
“Small but sustained changes in activities of daily living can profoundly affect energy balance,” said Eric Ravussin of the Pennington Biomedical Research Center in Baton Rouge, La.
Weight gain occurs when energy intake exceeds energy expenditure. If obese people could move around two more hours a day, Levine said, they could stave off an extra 20 pounds a year.
Levine, who is lean, was so impressed with the potential of his findings that he installed a treadmill in his laboratory office – arranged so he can talk on the phone and use the computer even as he moves.