Overall , the current literature supports clearly the dose-response relationship between physical activity and the seven chronic conditions identified .
Moreover , higher levels of physical activity reduce the risk for premature all-cause mortality .
The current Canadian guidelines appear to be appropriate to reduce the risk for the seven chronic conditions identified above and all-cause mortality
This systematic review examines critically the scientific basis for Canada 's Physical Activity Guide for Healthy Active Living for adults .
Particular reference is given to the dose-response relationship between physical activity and premature all-cause mortality and seven chronic diseases ( cardiovascular disease , stroke , hypertension , colon cancer , breast cancer , type 2 diabetes ( diabetes mellitus ) and osteoporosis ) .
The strength of the relationship between physical activity and specific health outcomes is evaluated critically .
Physical Activity and Breast Cancer Risk: The European Prospective Investigation into Cancer and Nutrition
There is convincing evidence for a decreased risk of breast cancer  with increased physical activity . Uncertainties remain , however , about the role of different types of physical activity on breast cancer risk and the potential effect modification for these associations . We used data from 218,169 premenopausal and postmenopausal women from nine European countries , ages 20 to 80 years at study entry into the European Prospect i ve Investigation into Cancer and Nutrition .  Hazard ratios ( HR ) from multivariate Cox regression models were calculated using metabolic equivalent value – based physical activity variables categorized in quartiles , adjusted for age , study center , education , body mass index , smoking , alcohol use , age at menarche , age at first pregnancy , parity , current oral contraceptive use , and hormone replacement therapy use . The physical activity assessment included recreational , household , and occupational activities . A total physical activity index was estimated based on cross-tabulation of these separate types of activity . During 6.4 years of follow-up , 3,423 incident invasive breast cancers were identified . Overall , increasing total physical activity was associated with a reduction in breast cancer risk among postmenopausal women ( Ptrend = 0.06 ) . Specifically , household activity was associated with a significantly reduced risk in postmenopausal ( HR , 0.81 ; 95 % confidence interval , 0.70 - 0.93 , highest versus the lowest quartile ; Ptrend = 0.001 ) and premenopausal ( HR , 0.71 ; 95 % confidence interval , 0.55 - 0.90 , highest versus lowest quartile ; Ptrend = 0.003 ) women . Occupational activity and recreational activity were not significantly related to breast cancer risk in both premenopausal and postmenopausal women . This study provides additional evidence for a protective effect of  physical activity  on breast cancer risk . ( Cancer Epidemiol Biomarkers Prev 2007;16(1):36–42
Overall , the current literature supports clearly the dose-response relationship between physical activity and the seven chronic conditions identified .
Moreover , higher levels of physical activity reduce the risk for premature all-cause mortality .
The current Canadian guidelines appear to be appropriate to reduce the risk for the seven chronic conditions identified above and all-cause mortality
This systematic review examines critically the scientific basis for Canada 's Physical Activity Guide for Healthy Active Living for adults .
Particular reference is given to the dose-response relationship between physical activity and premature all-cause mortality and seven chronic diseases ( cardiovascular disease , stroke , hypertension , colon cancer , breast cancer , type 2 diabetes ( diabetes mellitus ) and osteoporosis ) .
The strength of the relationship between physical activity and specific health outcomes is evaluated critically .