We all know that aging is inevitable and even a good thing. We don’t want to keep people from aging, but we definitely want to help people age well and avoid some of the physical problems associated with aging. Enter: exercise.
Dr. Mark Tarnopolsky, professor of pediatrics at McMaster University in Hamilton, Ontario, was surprised to find that exercise kept a strain of mice from becoming gray prematurely. New research published showed that exercise reduced or removed almost every detrimental effect of aging in mice that had been genetically programmed to grow old at an accelerated pace.
The finding with regard to mice gives hope to the body of evidence that suggests exercise combined with excellent food choices can overcome genetic tendencies.
For the experiment, Dr. Tarnopolsky and his colleagues used lab rodents that carried a genetic mutation which affected how well their bodies repair malfunctioning mitochondria. Mitochondria combine oxygen and nutrients to create fuel for the cells, they are the power generators.
As we age, mitochondria can accumulate small mutations, and over time our system cannot repair them and mitochondria start malfunctioning and dying. Many consider this dying off of mitochondria to be an underlying cause of aging in mammals. As mitochondria falter, the fuel they supply dwindles and cells respond such that muscles shrink, brain volume drops, hair falls out or loses its pigmentation, and soon enough we are, in appearance and beneath, growing old.
So what happened to the mice?
All of the mice lacked the necessary repair mechanism for their mitochondria, so they developed malfunctioning mitochondria as early as 3 months (human 20 years). Half were allowed to exercise and half were not. At eight months, the half that did not exercise were frail, weak, and crippled, with spindly muscles, shrunken brains, enlarged hearts, shriveled gonads, and patchy, graying fur–all died before reaching a year of age.
The other half–the mice which were allowed to exercise–ran on a wheel for 45 minutes three times a week beginning at three months. At eight months they remained youthful with full pelts of dark fur, no salt-and-pepper shadings, and they maintained muscle mass and brain function with normal gonads and heart size. They still had the genetic mutation, but mitochondria had proliferated so much that they had enough with far fewer mutations than the sedentary mice. At 1 year, none of the exercising mice had died of natural causes.
The benefit of regular exercise has been known, and yet it continues to surprise in how beneficial it actually is and how much it affects the systems of the body.
Source: New York Times, “Can Exercise Keep You Young”
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