The conclusions of the study were strong, and dose-dependent. I.e. casual exercisers did much better than couch potatoes and heavy exercisers did much better than casual exercisers.
The groups were significantly different. The "obese" people in the study had BMIs of over 30. The "very obese" group had BMIs over 35. The "thin" people had BMIs under 25. Similarly, people with diagnosed hyper-tension were compared with those of low-risk blood pressures. A variety of fitness levels were examined, ranging from couch potatoes to daily (but not competitive) runners.
The study found that fitness had a protective effect against each of the other risk factors. In fact, the only other statistically independent predictor of mortality for men and women was smoking.
>Also, have the results of the study ever been replicated?
Yes. There have been a number of very large studies that have produced similar results.
S.N.Blair et al. 1989 "Physical fitness and all-cause mortality" JAMA Nov;262: 2395-2401 (over 13,000 subjects)
I.M.Lee 2003 "Physical activity in women: how much is good enough?" JAMA Sept 10;290(10) 1377-1378
C.D. Lee, S.N.Blair, and A.S. Jackson 1999, "Cardiorespiratory fitness, body composition, and all-cause cardiovascular disease mortality in men." Am J Clin Nutr. Mar;69(3):373-380.
The groups were significantly different. The "obese" people in the study had BMIs of over 30. The "very obese" group had BMIs over 35. The "thin" people had BMIs under 25. Similarly, people with diagnosed hyper-tension were compared with those of low-risk blood pressures. A variety of fitness levels were examined, ranging from couch potatoes to daily (but not competitive) runners.
The study found that fitness had a protective effect against each of the other risk factors. In fact, the only other statistically independent predictor of mortality for men and women was smoking.
>Also, have the results of the study ever been replicated?
Yes. There have been a number of very large studies that have produced similar results.
S.N.Blair et al. 1989 "Physical fitness and all-cause mortality" JAMA Nov;262: 2395-2401 (over 13,000 subjects)
I.M.Lee 2003 "Physical activity in women: how much is good enough?" JAMA Sept 10;290(10) 1377-1378
C.D. Lee, S.N.Blair, and A.S. Jackson 1999, "Cardiorespiratory fitness, body composition, and all-cause cardiovascular disease mortality in men." Am J Clin Nutr. Mar;69(3):373-380.