A new study suggests that obese women get
just one hour of vigorous exercise a year, while obese men don't do much better
at fewer than four hours.
The findings startled the researchers,
whose main focus was finding better ways to measure how much exercise people
From one chair to another
"They're living their lives from one
chair to another," said Edward Archer, a research fellow with the
Nutrition Obesity Research Centre at the University of Alabama at Birmingham.
"We didn't realize we were that sedentary. There are some people who are
vigorously active, but it's offset by the huge number of individuals who are
According to the US Centres for Disease
Control and Prevention, more than one in three people in the United States is
obese, a step above being overweight. Obesity boosts the risk of cardiovascular
problems such as heart disease and stroke, diabetes and some cancers.
One expert did note that the definition of
vigorous exercise was very limited in the study, and the researchers themselves
acknowledged that the device used to track physical activity did not measure
swimming or biking very well.
Read: One in four SA women obese
In the new study, researchers examined the
results of a 2005-2006 government survey of adults aged 20 to 74. Among other
things, the survey tracked the weight, diet and sleep patterns of nearly 2,600
Accelerometer devices were used to track
their movements, providing insight into how much they exercised.
sex a fat burner?
The study defined "vigorous"
exercise as activities that burn fat like jogging and jumping rope, but not
sexual activity. According to Archer, who was at the University of South
Carolina when the study was conducted, sex isn't as much of a fat-burning
activity as certain other kinds of exercise so it doesn't qualify as vigorous.
The researchers found that the average
obese woman gets the equivalent of about one hour of exercise a year. For men,
it's 3.6 hours a year.
"The data was there, but no one looked
at it and parsed it the way we did," Archer said. In the big picture,
"there is a great deal of variability; some are moving probably a fair
amount. But the vast majority [of people] are not moving at all."
The typical life
What kind of lives are the most inactive
people living? "I think they're living the typical life. They drive their
children to school, they sit at a desk all day long, they may play some video
games and they go to sleep," Archer said.
John Jakicic, chair of the department of
health and physical activity at the University of Pittsburgh, praised the study
but cautioned that its definition of "vigorous" is limited and not
based on a person's fitness level. For some very obese people, for instance,
just general walking could be considered vigorous, he explained.
Read: Weight guidelines for obese pregnant women
Huge health impacts
As little as 30 minutes of exercise five
days a week can stop weight gain and improve health, study author Archer said.
"People don't understand that [you] don't have to go to the gym and lift
weights and run marathons to have dramatic impacts on your body. Standing
rather than sitting, walking rather than taking your car, they have huge
impacts on your health over time."
Jakicic agreed that little changes can have
a big difference. "Traditional exercise approaches are not the way to try
to get obese people active – the barriers are just too great," he said.
"However, we showed a number of years ago that encouraging multiple brief
periods – five to 10 minutes two to three times per day – was an effective
way to get individuals active initially. Once they started to become more
active in this way, they started to add even more activity."
The study appeared recently in the Mayo
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