A study published June 1, 2010 in the Journal of Sports Science & Medicine revealed interesting results in a study titled, “Intensity and timing in life of recreational physical activity in relation to breast cancer risk among pre- and postmenopausal women.”
The study looked at 858 women within four age groups of 14-20, 21-34, 35-50, and over age 50 years. The results found that “vigorous physical activity at ages 14-20 and 21-34 years lowered breast cancer risk by at least 35% in premenopausal women and by at least 51% in postmenopausal women”.
Risk was also reduced in postmenopausal women who reported, on average, more than 1.74 hours per week of vigorous intensity recreational activity for those over the age of 50.
Interestingly, for “ moderate activity the relationships remained statistically significant only in postmenopausal women active during ages 14- 20 years.”
There are two take away messages from the study. First, this study supports the theory that recreational activity, particularly activity done early in life, is associated with a decrease in invasive breast cancer risk in post menopausal women. The second message is that among premenopausal women, only vigorous forms of activity may significantly decrease the risk.