Does physical exercise slow down aging? Many studies have indicated that this is the case. A more recent study by German researchers compared four groups of people. Two groups were trained professional athletes; the other two were not trained athletes but nonetheless healthy and nonsmoking. Specifically, the groups studied were:
- young professional athletes with average age of 20 years
- middle-aged professional athletes
- two groups of healthy nonatheletes aged matched to the groups above.
As indicator of aging, the researchers measured the length of telomeres – that part of the DNA at the end of the chromosomes which protects them from damage. Telomeres are considered as a biological clock within the cells and they shorten with age. A much too short telomere leads to cell death.
Blood samples were taken from the study participants and chromosomes and telomeres in the blood cells were analyzed. The results showed that telomeres of trained athletes are much longer than healthy compared to not physically trained individuals of matching age.
According to lead author Dr. Ulrich Laufs, professor of clinical and experimental medicine in the department of internal medicine at Saarland University in Homburg, Germany:
“The most significant finding of this study is that physical exercise of the professional athletes leads to activation of the important enzyme telomerase and stabilizes the telomere… This is direct evidence of an anti-aging effect of physical exercise. Physical exercise could prevent the aging of the cardiovascular system, reflecting this molecular principle.”
Telomeres are a hot topic these days. Elizabeth H. Blackburn, Carol W. Greider and Jack W. Szostak jointly received the 2009 Nobel Prize in Medicine or Physiology for their work on “how chromosomes are protected by telomeres and the enzyme telomerase”. Telomeres act as “end caps” to chromosomes and function somewhat like the trips of shoe laces, i.e. protecting the chromosomes from wear and tear and damage. Telomeres, however, also get damaged and become shorter with each cell division, e.g. with aging. At a critical point, the telomeres become too short and the cell dies. A longer telomere, however, indicates slower aging.
So why do athletes have longer telomeres?
The researchers believe that long-term physical exercise activates the enzyme telomerase which makes telomere DNA. This process slows down telomere shortening in the blood cells. The participants who have engaged in rigorous physical activity for many years showed a slower rate of age-dependent telomere shortening.
Dr. Laufs continues:
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