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 .
Changes in physical fitness and all-cause mortality. A prospective study of healthy and unhealthy men.
OBJECTIVE To evaluate the relationship between changes in physical fitness and  risk of mortality in men . DESIGN Prospect i ve study , with two clinical examinations ( mean interval between examinations , 4.9 years ) to assess change or lack of change in physical fitness as associated with risk of mortality during follow-up after the subsequent examination ( mean follow-up from subsequent examination , 5.1 years ) . SETTING Preventive medicine clinic . STUDY PARTICIPANTS Participants were 9777 men given two preventive medical examinations  , each of which included assessment of physical fitness by maximal exercise tests and evaluation of health status . MAIN OUTCOME MEASURES All cause ( n = 223 ) and cardiovascular disease ( n = 87 ) mortality . RESULTS The highest age-adjusted all-cause death rate was observed in men who were unfit at both examinations ( 122.0/10,000 man-years ) ; the lowest death rate was in men who were physically fit at both examinations ( 39.6/10,000 man-years ) . Men who improved from unfit to fit between the first and subsequent examinations had an age-adjusted death rate of 67.7/10,000 man-years . This is a reduction in mortality risk of 44 % ( 95 % confidence interval , 25 % to 59 % ) relative to men who remained unfit at both examinations . Improvement in fitness was associated with lower death rates after adjusting for age , health status , and other risk factors of premature mortality . For each minute increase in maximal treadmill time between examinations , there was a corresponding 7.9 % ( P = .001 ) decrease in risk of mortality . Similar results were seen when the group was stratified by health status , and for cardiovascular disease mortality . CONCLUSIONS Men who maintained or improved adequate physical fitness were less likely to die from all causes and from cardiovascular disease during follow-up than persistently unfit men . Physicians should encourage unfit men to improve their fitness by starting a physical activity program
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 .