Just 30 minutes of daily walking or doing household chores -- that's all you need, say two researchers presenting new findings at the American Association for Cancer Research annual meeting in Orlando.
Best to Start in Teen Years
Starting in teen years, and sticking with it into adulthood, provides the greatest cancer prevention benefit, reports lead researcher Charles E. Matthews with Vanderbilt University.
Matthews studied 832 women living in Shanghai who had endometrial cancer (cancer of the lining of the uterus), all between ages 30 and 69. The women provided information on exercise when they were adolescents and in adulthood.
- Women who exercised in teen years and adulthood were 30% to 40% less likely to develop endometrial cancer compared with women who got no exercise during these periods.
- Women who did the greatest amounts of common daily household chores during both periods of life reduced their risk by 30%.
- Women who exercised as kids, then quit, got no significant prevention benefits.
- Those who began exercising in adulthood got about a 20% increased protection.
Participating in higher levels of physical activities appeared to lower the effect of weight as a risk factor for endometrial cancer. Overweight women are at higher risk for endometrial cancer because their higher body fat can lead to higher production of estrogen.
Fewer Breast Cancer Deaths
The second study showed that women who exercise after a breast cancer diagnosis live longer.
That study of 2,296 women, all diagnosed with various stages of breast cancer, were followed for 16 years. The researchers showed that those who got regular physical activity beginning two years after a diagnosis lived longer, reports Michelle D. Holmes, a researcher with Harvard University.
"When a woman faces a diagnosis of breast cancer, she wants to know, 'What can I do to help myself,'" says Holmes. "We saw survival benefit for those who walked as little as one to three hours a week."
Women who engaged in even modest walking on a weekly basis greatly increased their survival:
- One to three hours: 19%
- Three to five hours: 54%
- Five to eight hours: 42%
- 24 or more hours: 29%
Overweight women had the most pronounced benefit, she says. The women who exercised more but got less survival benefit may have had more advanced cancer. They also may be women who, on hearing the diagnosis, decided to turn unhealthy lifestyles around -- like quitting smoking.
"We know that physical activity has been shown to improve quality of life," says Holmes. "But we conclude that physical activity can help them live longer."