Lives of the Cells

I sometimes wonder what people of the 22nd century will think about our current level of understanding of basic physiology and medicine. Surely, future generations will have a better and more profound grasp of the basic processes of life, from the effects of diet on health, to the value of exercise, to the mystery of aging.

I thought about this while reading a story in the NY Times that cited studies of "serious middle-aged longtime runners" that found significant differences at the cellular level, when compared to sedentary subjects.

How Exercising Keeps Your Cells Young

One study looked at the length of telomeres in white blood cells. I'll quote the article here:

"Telomeres are tiny caps on the end of DNA strands... When cells divide and replicate these long strands of DNA, the telomere cap is snipped, a process that is believed to protect the rest of the DNA but leaves an increasingly abbreviated telomere. Eventually, if a cell’s telomeres become too short, the cell ‘either dies or enters a kind of suspended state... Most researchers now accept telomere length as a reliable marker of cell age."

The study found that the cells of the athletes had longer telomeres, meaning that the cells were "younger," or rather had resisted aging more effectively. In other words, the athletes who had kept on running and competing into middle age had bodies full of "younger" cells. Another study correlated the presence of younger cells with maximum oxygen capacity.

I think at some level we all know this to be true on the macro level -- if you keep training, you'll slow down less. But still, it's very intriguing to understand what's happening deep in the cells that might explain why it is true.