(RxWiki News) Moderate to vigorous exercise nearly every day of the week as a young adult will stave off excess pounds in middle age, women especially benefit.
"Everyone benefits from high activity, but I was surprised by the gender differences," said lead author Arlene Hankinson, M.D., an instructor in preventive medicine at Northwestern University Feinberg School of Medicine where to new research came from. "It wasn't that activity didn't have an effect in men, but the effect was greater in women. Now women should be especially motivated."
Over the course of 20 years, women who engaged in high levels of activity were shown to gain an average 13 pounds less than those with low activity. In men that number decreased to six pounds, however. This could be attributed, in part, to high-activity men eating more than their low-activity counterparts. (High activity included about 150 minutes of moderate to vigorous physical activity per week, including recreational activities such as basketball, running, brisk walking and exercise classes.)
Another reason for the gender weight-gain disparity: Men may overestimate their high-activity levels.
"Men may not be getting as much activity as they report," Hankinson said.
Men maintaining high activity gained 1.2 fewer inches in waist circumference and women maintaining higher activity gained 1.5 inches less than their lower-activity counterparts.
Participants (1,800 women and nearly 1,700 men) comprise part of the Coronary Artery Risk Development in Young Adults (CARDIA) study, a multi-center, longitudinal and population-based observational study designed to describe the development of risk factors for coronary heart disease in young black and white adults.
"This paper is another example of how the CARDIA study has contributed to our knowledge about the importance of initiating healthy habits early in life and vigilantly maintaining them," said paper coauthor Stephen Sidney, M.D., associate director for clinical research at the Kaiser Permanente Division of Research. "Common medical problems such as heart disease, diabetes and obesity have their origins in childhood and can generally be prevented by maintaining a normal weight, not smoking, exercising regularly and eating a healthy diet throughout life."
More than 30 percent of the adult American population is obese, a figure that has increased dramatically since 1976.
Weight gains in people with moderate or inconsistent activity levels were similar to those in the low-activity group.
"Women seemed to benefit the most from maintaining higher activity; the magnitude of weight change was more than twice as large among women compared with men," the authors conclude. "Similarly, participants who maintained the Health and Human Services-recommended 150 minutes of moderate activity per week gained significantly less weight compared with participants who did not."
This is the first study to measure the impact of high activity over 20 years between young adulthood and middle age while examining participants (seven times) over the course of the study.
As metabolic rates diminish as we grow older, we develop conditions or lead lifestyles conducive to weight-gain.
"The study reinforces that everyone needs to make regular activity part of their lifestyles throughout their lives," Hankinson said. "Not many people actually do that."
Only 12 percent of the study's participants ranked in the high-activity category.