This is good news and bad news. Older exercisers seem to have younger, healthier cells. Good news that you can keep your cells younger. Bad news that you have to exercise.
A study reported in the Washington Post looking at 2,400 pairs of twins suggests that those twins that exercised in their spare time over a 10 year period may have healthier and younger cells than those that did not exercise.
The study indicates that exercise may slow the loss of the ends of chromosomes which are the strands of DNA that contain our genetic material. (The image is of magnified stained chromosomes from Drosophila (the fruit fly). The ends of chromosomes are a special region and are called telomeres. Telomeres are thought to help protect chromosomes.
As we age and our cells divide, DNA is trimmed from the ends of the chromosomes and the telomeres become shorter. The length of telomeres is an indicator of age. Several diseases that cause premature aging have been shown to have fast rates of telomere shortening.
The lead researcher for the study Tim Spector said,
“The length of the twins’ telomeres was directly related to their activity levels, the researchers found. People who did a moderate amount of exercise — about 100 minutes a week of activity such as tennis, swimming or running — had telomeres that on average looked like those of someone about five or six years younger than those who did the least — about 16 minutes a week. Those who did the most — doing about three hours a week of moderate to vigorous activity– had telomeres that appeared to be about nine years younger than those who did the least.”
Another study, that is not published yet, is reported in the NYT. In this study looked at two age groups, those in their mid 20’s and a second group that had an average age of 51. Within these two groups some were inactive and some were running 45 to 50 miles per week. For all those in their 20’s there was little difference in telomere length, but for the older group the very active group had less telomere shortening. The older runners had longer telomeres than those who were inactive, but were not as short as those in their 20’s.
There is quite a bit of evidence that endurance type exercise is bad for the body, damaging mitochondria (powerhouses of cells and involved in oxidation) and some evidence of increased telomere shortening. So probably doing much more running than 50 miles per week, the damaging effects would perhaps start to show up. So there is probably an optimal amount of exercise for slowing aging.
The first study suggests that any amount of exercise will have some impact on aging of cells. So get out there for a walk or a bike ride to keep your cells younger.
photo credit: Image Editor
