Americans are exercising more, but that has not done much to slim their waistlines, underscoring the immense challenge confronting health advocates fighting the nation’s obesity crisis.
In more than two-thirds of U.S. counties — Â€” including some of the most unhealthy — Â€” men and women became more physically active over the last decade, according to data published Wednesday.
Women made notable progress nationwide, with the percentage who got sufficient weekly exercise jumping from 46.7 percent to 51.3 percent. The percentage of physically active men ticked up a point to 57.8 percent.
But these improvements have done little to reduce obesity, researchers at the University of Washington’s Institute for Health Metrics and Evaluation concluded.
Between 2001 and 2009, obesity rates for men or women fell in just nine counties. National rates climbed throughout the decade, although some recent evidence suggests obesity rates may no longer be rising.
“Â€œThere has been a lot of progress on physical activity,”Â€ said Dr. Christopher Murray, lead author of the research, which was published in the journal Population Health Metrics. “Â€œTo tackle obesity, we need to do this. But we probably also need to do more. … Just counting on physical activity is not going to be the solution.”Â€
Today, more than one-third of U.S. adults and approximately 17 percent of children are obese, according to the federal Centers for Disease Control and Prevention.
Many health experts believe that changing diet may do more to bring those numbers down than increasing exercise.
A separate paper by the institute published Wednesday in the Journal of the American Medical Association identified poor diet as the No. 1 factor contributing to AmericaâÂ€™s poor health compared to other industrialized nations.
Life expectancies in the United States stagnated for women in 1,405 counties and for men in 154 counties between 1985 and 2010, researchers reported. And Americans living in the worst-performing counties in the nation, in Appalachia, now live shorter lives than people in Vietnam, Yemen and Sudan.
Despite the grim news, Murray and others believe that, eventually, the uptick in exercise will likely deliver significant health benefits and may help reverse the decades-long increase in weight.
“We know that exercise has amazing virtues,”Â€ said Dr. Georges C. Benjamin, executive director of the American Public Health Association. “It helps prevent cardiovascular disease, build muscle tone and reduce bone loss. It improves mental health, and it reduces stress. … All of those are vitally important.”Â€
Some of the biggest gains in physical activity over the last decade occurred in America’Â€™s unhealthiest counties in the Deep South and Appalachia.
The percentage of women in Morgan County, Ky., exercising enough each week jumped 18.3 percentage points between 2001 and 2009 to 44 percent, the biggest improvement researchers found.
The biggest gain for men occurred in Concho County, a small, rural county in west-central Texas, where the percentage of men who got enough physical activity increased 16.7 percentage points to 58.2 percent.
Overall, six of the 10 counties that improved most for men and seven of the 10 that improved most for women are in Kentucky. Counties around Atlanta, Los Angeles, San Francisco, San Diego, Houston and Denver also saw major improvements, according to the report.
Researchers defined sufficient physical activity as 150 minutes of moderate activity a week or 75 minutes of vigorous activity.
Obesity in Mexico surpasses U.S.
Mexico has surpassed the United States in levels of adult obesity, though the country remains far below levels found in some island nations and parts of the Middle East. Mexican activists and academics are expressing concern about the dubious distinction, noting that some Mexicans remain malnourished while others are becoming obese. The U.N. Food and Agriculture Organization says in a recent report that 32.8 percent of Mexicans suffer obesity, compared to 31.8 percent of Americans. Egypt clocks in at 34.6 percent and Kuwait at 42.8 percent, though they are still far below the 71.1 percent-level of Nauru, a Micronesian island state in the Pacific. Activists said Wednesday that Mexico’s adoption of processed foods and the abandonment of the country’s traditional diet have contributed to a severe obesity problem.