Absence may make the heart grow fonder, but endurance exercise seems to make it younger. According to a study conducted at Washington University School of Medicine in St. Louis, older people who did endurance exercise training for about a year ended up with metabolically much younger hearts. The researchers measured heart metabolism in sedentary older people. At the start of the study, they found that in response to increased energy demands, the hearts of the study subjects didn’t increase their uptake of energy in the form of glucose (blood sugar). But after endurance exercise training, the participants’ hearts doubled their glucose uptake during high-energy demand, just as younger hearts do.
ENDURANCE EXERCISE SEEMS TO MAKE THE HEARTS OF OLDER PEOPLE BEHAVE MORE LIKE THE HEARTS OF YOUNGER PEOPLE. CARDIOLOGY RESEARCHERS AT WASHINGTON UNIVERSITY SCHOOL OF MEDICINE IN ST. LOUIS HAVE FOUND THAT FOLLOWING EXERCISE TRAINING, OLDER HEARTS USED MORE GLUCOSE DURING PERIODS WHEN THE HEART NEEDED EXTRA ENERGY. JIM DRYDEN REPORTS
AS WE GET OLDER, OUR HEARTS GET LESS EFFICIENT, AND OUR RISK FOR HEART DISEASE INCREASES. SOME OF THAT MAY BE BECAUSE AS WE GET OLDER, WE TEND TO BE LESS ACTIVE, ACCORDING TO WASHINGTON UNIVERSITY CARDIOLOGY RESEARCHER PABLO SOTO.
(act) :20 o/c those changes
Even if you dont develop any heart disease, the heart function
deteriorates, and people, even if they otherwise stay healthy,
tend to develop heart failure as they get into extreme old age.
So we wanted to look at some of the changes that occurred in the
heart as you get older and see if there was the potential to
reverse some of those changes.
ONE OF THOSE CHANGES INVOLVES HOW THE HEART USES ENERGY. A HEALTHY HEART GETS ABOUT 70 PERCENT OF ITS ENERGY FROM FATTY ACIDS AND ABOUT 30 PERCENT FROM GLUCOSE. THEN WHEN ITS SUBJECTED TO THE STRESS OF EXERCISE, THE HEART RAMPS UP ITS USE OF BOTH FATTY ACIDS AND GLUCOSE. BUT SOTO SAYS OLDER HEARTS ARE MUCH LESS LIKELY TO INCREASE GLUCOSE METABOLISM THAN THEIR YOUNGER COUNTERPARTS. HIS TEAM STUDIED HEALTHY-BUT-SEDENTARY OLDER ADULTS. A GROUP OF 6 OLDER MEN AND 6 OLDER WOMEN DID 11 MONTHS OF ENDURANCE EXERCISE TRAINING.
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All individuals across both genders improved their glucose use
to levels that were very similar to what we saw in our previous
study with young individuals. This indicated to us that at least
the metabolic changes associated with aging could be, potentially,
reversed with exercise training.
SOTO SAYS HES NOT CERTAIN WHAT THE FINDINGS MEAN TO THE RISK FOR HEART PROBLEMS BECAUSE ALL OF THE PEOPLE IN THE STUDY WERE OLDER AND SEDENTARY, BUT THEY DIDNT HAVE HEART DISEASE.
(act) :12 o/c those individuals
Results of the study might have been different if we were studying
patients that had heart disease already and had a heart attack or
had bypass surgery. But other investigators have shown that exercise
is also beneficial for those individuals.
SOTO SAYS A POSSIBLE EXPLANATION FOR THE DIFFERENCES IN THE HEARTS GLUCOSE METABOLISM BETWEEN OLDER AND YOUNGER PEOPLE COULD BE THAT THE OLDER PEOPLE HAVE DEVELOPED THE VERY BEGINNINGS OF HEART FAILURE, WHICH WONT DEVELOP FULLY UNTIL THEY REACH THEIR 80s OR 90s. HE PLANS TO STUDY THAT IDEA BY LOOKING AT THE EFFECTS OF EXERCISE ON THE HEARTS GLUCOSE METABOLISM IN PEOPLE WHO ALREADY HAVE BEEN DIAGNOSED WITH HEART FAILURE.
(act) :30 o/c beneficial effect
Older individuals, the way we see it, even though their hearts
pumping well, the pattern of their metabolism suggests that heart
failure is starting to develop. So what we suspect is that if we
do this same study in individuals that already have heart failure
from other reasons, perhaps we can improve their metabolic profile.
So, indeed, other investigators that have not looked at metabolism
have showed that exercise is beneficial for individuals with heart
failure, but the big question is why? What is it that has the
SOTO REPORTED HIS FINDINGS IN THE AMERICAN JOURNAL OF PHYSIOLOGY, HEART AND CIRCULATORY PHYSIOLOGY. IM JIM DRYDEN