(LOS ANGELES) -- Researchers at the Stanford University Medical Center say that the surge in the American obesity rate is linked to a lack of exercise, not a dramatic change in the overall number of calories consumed.
The study was conducted using data from national health surveys from 1988 through 2010, and led researchers to link "huge increases in both obesity and inactivity." Data was culled from 17,430 survey participants between 1988 and 1994 and 5,000 each year between 1995 and 2010. Each participant was asked to record the frequency, duration and intensity of their exercise over the last month.
Researchers defined "ideal" exercise as over 150 minutes per week of moderate exercise or over 75 minutes per week of vigorous exercise.
The study only found a link between lack of activity and obesity, not a causation.
In 1988, just 19 percent of women and 11 percent of men reported no physical activity -- figures that climbed to 52 percent and 43 percent respectively by 2010. During that same time, obesity rates climbed from 25 percent among women and 20 percent in men to 35 percent in both women and men.
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