Interesting article in Sports Illustrated this week about genetics and athletic performance.

Yannis Pitsiladis, a biologist at the University of Glasgow, selected 24 gene variants most often associated with sprinting or endurance prowess and looked for them in the genomes of four men who have held the world record in the 100-meter dash and five who have held the world record in the marathon. What he saw was that based on those genes, the world-beaters are not genetic outliers at all. Pitsiladis analyzed the DNA of some of his graduate students for comparison and found that “a student of mine has a better rating for sprinting than the likes of an Asafa Powell or Usain Bolt.” (Pitsiladis is legally prohibited from identifying specific athletes with their genetic material, so he used Powell and Bolt as rhetorical examples.)

That rather startling result leaves two broad possibilities: First, there is a tremendous amount of work left to be done to find all the remaining genes that contribute to athletic success; second, something other than genetics is at work. Both may well be true, but only time and more research will rule on the former, while Pitsiladis has compiled considerable data on the latter.

Overall, it looks like many factors — not just genetics shape who we are.

“Genes do not act in a vacuum,” notes Bernd Heinrich, a biologist and author and the 1981 North American 100K champion. Heinrich, who grew up running to school, insists that “genes are very plastic. They can be turned on or off. Look at a caterpillar and a butterfly: They’ve got the same genes. One flies, and one can barely crawl.”

So, don’t blame your genetics for being out of shape.  Just get to work.