I just came across a news report on the Times Online website by Nigel Hawkes, entitled, Exercise really can make you younger, study shows. A team from King’s College London looked at telomeres, a section of repeating DNA at the end of chromosomes, in twins to judge how exercise affected them. Telomeres protect the end of chromosomes, and they shorten over our lives (however, long telomeres may increase the likelihood of cancer, so there’s a trade-off between cancer susceptibility and aging). A study in 2002 even showed that telomere length could be used in forensic anthropology to tell the age of remains. The researchers used questionnaires, but they also looked at data from twin studies, to try to isolate the effects of exercise, controlling for BMI, smoking, diet, and even genetic inheritance (hence, the twins).
The difference could be pretty significant. Dr Lynn Cherkas from King’s College explained: ‘Overall, the difference in telomere length between the most active subjects and the inactive subjects corresponds to around nine years of ageing.’ According to the researchers, their results ‘show that adults who partake in regular physical activity are biologically younger than sedentary individuals.
‘The only reason I point out the research on the Neuroanthropology blog is that here we have another cellular-level mechanism that profoundly affects very basic body functioning that can be manipulated by individuals, behaviour, cultural ideals, social fads, and even moral panics. The amount of exercise we get affects the speed at which our cells age; but the amount of exercise we get is, in turn, affected by a whole range of things, from changing policy and budget concerns at schools, to safety concerns about transportation, housing patterns, leisure activities, public health campaigns… In other words, we have a wonderful example in the current discussion of exercise, and the effects of exercise on our telomeres, of a way that sociological-scale phenomena might affect very microscopic-scale qualities of the human body. The shape of our DNA is not just a cause of our physiology, but also an effect of our physical activity.