It remains unclear the amount or intensity of exercise that is needed to produce this effect and at what age the physical activity must occur. The study consisted of a group of 74,171 women aged 50-79 from 40 U.S. clinical centers between 1993-1998 for the Women’s Health Initiative Observational Study.
Information collected was based on factors such as medical, family history, physical activity, diet, height, weight and lifetime use of hormone therapy.
In a four-and-a-half year follow-up of the study, breast cancer was newly diagnosed in 1,780 of the women. The study also revealed that women who participated in regular strenuous physical activities at the age of 35 decreased their risk of breast cancer by 14 percent compared with less active women.
This is further evidence that exercise before and after menopause are linked to breast cancer prevention. The effect was realized even with small increments of exercise equivalent to one to two hours per week of brisk walking. The results have shared similarities to those associated with decreasing the risk of cardiovascular disease among postmenopausal women and those with diabetes.
Canadian Medical Journal March 2, 2004;170(5) (Free Full Text Article)
This association is not a new one. I posted an article three years ago on this topic, however I suspect it might be an unusual connection for some readers. For nearly four decades, I have been an avid exerciser and obviously expressed a great interest in health, but when I first read the association I was somewhat surprised as it is not intuitively obvious.
Getting exercise and good old cardio combined with some strength training does just about everything right for you, however you shouldn’t rely solely on exercise to prevent cancer. It is my belief that omega-3 fats such as cod liver oil are likely to be even more important than exercise.
Another powerful way to reduce cancer risk is by avoiding sugar. Omega-3, avoiding sugar and exercise are good for preventing just about any type of cancer. One final caution that can be used for breast cancer prevention is to avoid estrogen unless you’ve had your ovaries removed. There are some other strategies that work quite well for breast and prostate cancers for those who are interested.