Effect Of Exercise On Actual Disease Incidence And Longevity

>increased the life spans of animals allowed to eat
It must be admitted that while the risk factorsas much as they desired, but decreased the
are certainly altered, conclusive long term followother wise very extended life spans of the calorie
up studies confirming the positive effects ofrestricted animals. This means that the relationship
exercise training on susceptibility to coronarybetween diet and exercise is complex. They are
artery disease and heart attacks have been slownot simply additive. Exercise does not
to materialize.  In the National Exercise and Heartautomatically increase life span, as everyone
Disease Project, a supervised exercise programseems to think. A fine tuning between exercise
displayed only a marginal effect on 3 yearand diet is necessary for the optimal effects. And
mortality and 3 year frequency of repeat heartpeople who do crash dieting, or nutritionally
attacks in patients who had already suffered one.unsound dieting, and couple it with vigorous
But a recent large follow up study of 16,936exercise to "burn off" even more calories are
Harvard alumni from 1962 to 1978 did indicatedoubling the harm of their bad dieting technique.
that habitual post college exercise rather thanDetailed diet exercise experiments are being
amount of athletic participation as studentsperformed by scientists at Washington University
coincided with a low death rate from heartin St. Louis, in the laboratory of Dr. John Holloszy,
disease. Sedentary alumni, even former varsitywhom I consider one of the best exercise
athletes, were at higher risk. But while the deathphysiologists in the world. The studies compare
rates declined as the amount of exercisefully fed sedentary rats, fully fed and exercising
increased from less than 500 to more than 3,500rats, and calorie restricted sedentary rats. At time
kilocalories per week, beyond 3,500 the deathof writing, 50 percent of the fully fed exercising
rate increased slightly. The Pritikin group haverats were alive at months of age compared with
presented evidence that their program of diet andonly percent of the fully fed sedentary rats. But
exercise inhibits the progression of peripheralagain the calorie restricted non exercising rats
vascular disease, coronary arteriosclerosis, andwere surviving the longest. The fat cells of fully
adult onset diabetes. But their studies do notfed sedentary rats were resistant to insulin, those
differentiate between the benefits of diet andof diet restricted animals sensitive to insulin, and
those of exercise. A common fallacy aboutthose of exercisers still more sensitive . Blood
exercise and heart disease is that exercise ischolesterol levels followed the same patterns. So
more effective than diet in preventing an attack.in this important study the exercising rats seem
That's not true. The idea that diet is rather"fitter" than diet restricted sedentary rats, but
irrelevant as long as you exercise strenuously is atheir survival is less. This can any mean, as I've
myth. Jim Fixx, author of the 1977 best seller Thealready indicated, that fitness biomarkers are not
Complete Book of Running, who transformedentirely equivalent to longevity biomarkers. But
himself from a chubby 2l4 pound, two pack a daywe must await further studies from Holloszy's
smoker into a sleek 160 pound marathon runner,laboratory to clarify these important issues.
died at the age of 52 from .a heart attack whileRecommendations
pounding the road in Vermont. He paid dearly forThe overall evidence suggests that aerobic
his expressed belief that running all by itself wouldexercise considerably increases cardiovascular
suffice to prevent heart disease. Do not fall sofitness and substantially decreases the
deeply into the myth of exercise that you neglectsusceptibility to heart attack and that it improves
other preventive health measures. Diet is thesome features of carbohydrate metabolism. But
most important, even for heart disease, althoughat the same time possibly owing to an increased
exercise provides additional benefit. But there isgeneration of free radicals or a temporary
absolutely no evidence in either animals or humansincrease in metabolic rate­it may slightly
that exercise influences the rate of cancer, theaccelerate the basic rate of aging. Exercise
second major cause of death after cardiovasculardefinitely has a good effect and possibly a mild
disease, and we know that cancer is very heavilybad effect. The fitness effect increases rapidly up
influenced by diet.to a certain point as you exercise more and
The Interplay Between Diet And Exercisemore, but beyond that point the benefit may level
Let us consult a study made by scientists at theoff. According to Dr. Kenneth Cooper of Dallas,
National Institute on Aging. They allowed onerunning tops out its aerobic benefits at 15 miles a
population of mice to eat as much as theyweek. He says, "If you run more than that, it's
wanted, but gave them no access to exercisefor some thing other than fitness." Others agree
wheels; a second population ate as much as theywith this assessment. My own view is that the
wanted but also exercised daily; a third populationoptimal combination for health and longevity is the
was calorie restricted and not allowed to exercise,high low diet plus the equivalent in aerobic
and a fourth, calorie restricted population wasexercise of about 15 miles of jogging per week,
allowed to exercise. What were the life spans ofcoupled with a modest amount of weight
these populations? shows the results. Exerciseresistance training .