Doyle agreed that many mechanisms are probably at work. Activity can improve immune function, for instance, and help control weight, and that in turn can decrease inflammation, she said.
To achieve cardiovascular fitness and reduce cancer risk, be moderately active 150 minutes a week or vigorously active for 75 minutes, or some combination, Doyle advised.
Because this study is being presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.
Lakoski found a link between fitness and cancer protection, not cause and effect. She also can't say whether the findings would apply to women. She hopes to study that next.
To learn more about physical activity guidelines and cancer prevention, see the American Cancer Society.
SOURCES: Susan Lakoski, M.D., assistant professor, internal medicine, University of Vermont, Burlington; Colleen Doyle, M.S., R.D., director, nutrition and physical activity, American Cancer Society; June 2, 2013, presentation, American Society of Clinical Oncology annual meeting, Chicago
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