Only a tiny fraction of Americans heed the advice to take part in moderate or vigorous activity to keep weight down and stay healthy, and when they do, they're likely to do something a little self-defeating: prepare food.
Those are two key findings of a study published Wednesday in the American Journal of Preventive Medicine.
For the study, researchers from Pennington Biomedical Research Center in Louisiana analyzed data collected between 2003 and 2008 from nearly 80,000 respondents for a nationwide survey in which Americans were asked what activities they did in the preceding 24 hours.
Only 5.07 percent of Americans reported doing any vigorous-intensity activity like running, while at the other end of the scale, more than 95 percent said they had engaged in the highly sedentary activity of eating and drinking.
The next most common activity was another sedentary one -- watching television or a movie, which eight in 10 Americans did.
The "most frequently reported moderate activities were food and drink preparation (25.7 percent), followed by lawn, garden, and houseplant care (10.6 percent)," the study said.
Lead author of the study Catrine Tudor-Locke said knowing what kind of activities Americans do "can inform intervention strategies aimed at improving energy balance," or the balance of calories consumed by eating and drinking compared to calories burned through physical activity.
A separate study published last month in the same medical journal found that Americans' overall lifespans and the years they live in good health have been slashed as the percentage of obese adults has shot up.
In 16 years, the obesity rate in the United States soared by 90 percent, from 14 percent in 1993 to 27 percent two years ago, that study found.
It also found a strong correlation between modifiable lifestyle choices, such as a lack of physical activity, and the rising burden of obesity.
Explore further: 'Beyond aid' in health care: Is it time for scrutiny?