rrr wrote:
Fitness is not even that necessary. With a great diet you will be thin, low cholesterol and blood pressure, no diabetes, low cancer risk.
diet beats exercise by a wide margin.
incorrect, my friend.
Both have many positive effects on one's health. However, one of the strongest predictors of health (longevity, CVD risk, etc) is FITNESS (cardiorespiratory fitness/exercise capacity) . This holds true for even former smokers, and overweight people. As you age, if you can hop on a treadmill and score in the top 20%, or even better, top 10%, of people your age for a cardio fitness test, you will be much less likely to die than someone in the lower brackets. Diet alone will not achieve this.
You can't eat a low-cal, healthy diet and not be active at all and be very healthy (fairly healthy maybe). Furthermore, the amount of time one spends sitting is another major predictor of all cause mortality. So if you sit all day long, are very sedentary and hardly move around at all each day, yet eat extremely healthy and are thin, the odds of your overall health being robust are low.
Fitness matters. A lot. And sure, it doesn't have to be extreme fitness, but taking walks every day, at a fairly hard pace, will even do the trick.
http://www.ncbi.nlm.nih.gov/pubmed/20697029Exercise capacity and mortality in older men: a 20-year follow-up study.
CONCLUSIONS:
Exercise capacity is an independent predictor of all-cause mortality in older men. The relationship is inverse and graded, with most survival benefits achieved in those with an exercise capacity >5 METs. Survival improved significantly when unfit individuals became fit.
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Being highly fit negates many of the negative effects of being overweight/obese-
http://www.ncbi.nlm.nih.gov/pubmed/19617881(this is from a commentary on the above article-
"Our study showed that cardiorespiratory fitness (CRF) is related to coronary heart disease-related death in hypertensive and normotensive men, and as well as in obese and nonobese men. Similar findings have been found in those with different combinations of common risk factors. In previous studies too, investigators have consistently observed that low CRF is related to the risk of death in normal weight, overweight, and obese subjects. These findings support those from cohort studies suggesting that the risk of death associated with low CRF is comparable with those associated with conventional risk factors including smoking, hypertension, hypercholesterolemia, obesity and diabetes."