Another new study has hit the papers. As we age, the very DNA in our trillions of cells starts to fray, unravel and disintegrate. But now it appears that exercise (read: kayaking) can delay the inevitable. A study published yesterday hints that fitness buffs appear to have "younger" DNA than the chronically sedentary.
However, we have been cautioned that the old chicken-and-egg question - does exercise preserve healthier DNA, or does healthier DNA enable people to exercise more? - has yet to be answered.
The study's authors examined just the ends of DNA strands. Called telomeres, these act something like the plastic caps on shoelaces (an aglet, my brother tells me), preventing the DNA in chromosomes from unraveling. Previous research has shown that older people have shorter ends than younger folks. Indeed, biologists say they shrink every time a cell divides. This study found that heavy exercisers (those who put in more than three hours a week running, cycling, pumping iron, or other vigorous activity - say, kayaking...) had relatively long telomeres - comparable to those of couch potatoes 10 years younger.And something that I've known for years was mentioned: "People who choose to exercise are different in so many ways from people who don't." Oh, yeah.