In the study, scientists looked at telomeres, which are the DNA that protects the ends of chromosomes from damage. The longer the telomeres, the more protection the chromosome has. As we age, telomeres gradually shorten and act as a sort of biological clock, limiting cells to a certain number of divisions. When the telomeres become critically short, the cell dies.
The researchers measured the length of the telomeres in two groups of athletes and two groups of non-exercisers. The telomeres of the athletes were longer and, apparently, more efficient than those of the non-exercisers. As the body's cells grow and divide, the telomeres are similar to the ends of shoelaces that prevent the ends of the chromosomes from fraying. In addition, animal studies reveal that exercise helps regulate telomere- stabilising proteins, which protect the cell from deterioration and cell death.
Ulrich Laufs, M.D. is the study's lead author and professor of clinical and experimental medicine in the department of internal medicine at Saarland University in Homburg, Germany. He says, "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."
Laufs team analysed 32 young (average age 20) professional runners and compared them with middle-aged athletes (average age 51). Those groups were compared with healthy non-exercisers who were age-matched to the athletes. Not surprisingly, the athletes were more fit than the non-exercisers, had a lower resting heart rate, lower blood pressure, and lower body mass index. The loss of telomeres usually seen with aging was found to be significantly less in the middle-aged athletes than in the middle-aged non-exercisers.
"Our data improves the molecular understanding of the protective effects of exercise on the vessel wall and underlines the potency of physical training in reducing the impact of age-related disease," Laufs said.