According to New York Times health and science columnist Gina Kolata, "Elite distance runners have physiological traits that make them faster than the rest of us and account for the albatross between Olympic champions and the masses of fitness and recreational runners."
As a fitness runner, Kolata learned that lesson when she went on a three-mile run and tried to keep up with her son, a college All- American in cross country and track.
"I always knew there was a fundamental difference between him and me when it came to running far and fast," said Kolata in her recent column, headlined, "Why Joggers Labor and Olympians Fly."
"We still run together, but all that means is that we start out at the same place and end up at the same place."
Researchers suggest elite distance runners share three inborn, physiological traits that separate them from fitness and recreational runners:
Consistent running and hard work allow runners of all ages and ability levels to improve. Motivation also makes a difference. But, unless heredity has dealt you some physiological trump cards, it is a long, if not impossible, road to the top.
VO2 MAX is the volume of oxygen a runner can consume during maximum exertion or an all-out effort.
"Athletes with a high VO2 MAX can pump large volumes of blood to the exercising muscles, usually because they have very large and powerful hearts," said Paul Risbish, Ph.D., an exercise physiologist and a runner at Wake Forest University.
"To put it in perspective, the heart of an average adult during exercise pumps out about 15 to 18 liters of blood per minute. The heart of an elite distance runner typically pumps out 30 to 35 liters of blood per minute during strenuous exercise."
VO2 MAX increases with training, which means as runners get fitter, their times at various running distances continue to improve. But good, old-fashioned hard work and training only take you so far.
Elite distance runners are blessed with bigger, stronger and more powerful cardiovascular systems. Exercise physiologists say that even when elite athletes are out of condition -- when they haven't run for several months or longer -- they still have VO2 MAX values significantly higher than those of a fitness or recreational runner.
The second characteristic of elite runners is, they are extremely efficient, exerting themselves less than slower runners at any given pace.
According to Kolata, in a study of elite runners, good runners and recreational joggers, Don Morgan, Ph.D., an exercise physiologist and recreational runner at Middle Tennessee State University, and his colleagues found that the better the runners were, the less effort they exerted running at a particular pace.
The third characteristic of elite runners is the ability to continue to run at near maximum effort or at their anaerobic threshold.
"That pace," says David Martin, an exercise physiologist at Georgia State University, is: "When the conversation stops and the hard work begins. ... If you can carry on a conversation while you are running, you have not reached it."
Runners' abilities to run at their anaerobic thresholds, like their VO2 MAX, improves with training, but elite athletes have a genetically higher threshold.
John Bobalik is an exercise physiologist and coordinator of Purdue University Calumet's Fitness Center. He can be reached by e-mail at firstname.lastname@example.org.