More U.S. adults are getting physical _ or at least that's what they're telling researchers.
A national telephone survey found the percentage of women who report regular physical activity rose to about 47 percent in 2005, up from 43 percent in 2001.
The percentage of men reporting regular exertion rose to about 50 percent, from 48 percent.
The small but significant increases are considered good news, but also seem a little perplexing: U.S. obesity rates are not declining, and there are indicators that some weight-related conditions _ such as heart disease _ are getting worse in some adults.
Recent increases in physical activity may not yet be affecting some health indicators, said Teresa Moore, an associate professor of exercise science at the University of South Carolina.
Or perhaps some people are exercising more but not taking other important steps, added Moore, who was not involved in the research.
"You could be out raking leaves, but if you're eating a high-fat, poor-quality diet, you may still be aggravating the problem," she said.
The survey was done by researchers at the U.S. Centers for Disease Control and Prevention. It is being published this week in Morbidity and Mortality Weekly Report, a CDC publication.
The researchers drew their data from surveys in 2001 and 2005 of noninstitutionalized adults who had landline telephones. About 205,000 people answered questions in the 2001 survey, and 356,000 in 2005.
People in the survey were asked about their physical activity in a usual week in their non-working hours. One question asked about moderate activities such as brisk walking or gardening. Another asked about vigorous activities such as running or heavy yard work.
Respondents were considered physically active if they had at least 30 minutes of moderate activity five or more days a week, or 20 minutes of vigorous activity three or more days a week.
Along racial lines, reported activity rates were highest among whites and lowest among blacks.
As for education level, college graduates exercised the most, and people without a high school education were the least active, the researchers found.
Other studies haven't shown overall exercise rates as high as 50 percent, said Julie Schwartz, a dietitian and fitness expert at Atlanta's Emory Healthcare hospital system.
The new report differed from another recent government survey that found leisure-time physical activity decreased in men and remained static for women from 2000 to 2005.
People often do not accurately recall how much physical activity they actually did, Moore said.