What makes an athlete an Olympian--better than anyone else in the World? Are some people born to be Olympians?
This is not an easy question to answer, but there is evidence that would suggest certain people are born more likely to be highly successful athletes than others. There are differences in the body type of a typical Olympian compared to that of an average person. Some of these differences are obvious, such as height and weight; some are not so obvious, such as cardiac efficiency and muscle composition.
New research has been directed at the study of the muscle composition of an Olympic caliber athlete compared to that of a typical person. Skeletal muscle comprises the largest percentage of the human body by mass. The skeletal muscles are made up of contracting fibers that allow our muscles to contract with force. There are two broad categories of muscle fibers, fast-twitch and slow-twitch. Depending on the composition of a given muscle, the contractile speed and the endurance of the muscle can vary greatly.
Most people know there are two types of skeletal muscle, because most people have made the critical decision at meal time: light or dark meat? The turkey we eat comes in two types, but most people don't bother to think why there are differences. The answer is that the skeletal muscle composition varies in different parts of the body of a turkey. The same is true in most animals, including humans. While this may not be as visibly obvious, some human muscles are almost all fast-twitch and some are almost all slow-twitch.
The difference between fast and slow twitch muscles is significant. The fast twitch muscle fibers can contract almost ten times more frequently than a slow twitch muscle. The slow twitch muscle is made to contract for longer periods of time without needing rest. An Olympic sprinter may have greater that 80% of their muscle as fast twitch, whereas a marathoner can have greater than 90% slow twitch muscle fibers. An average person has approximately equal amounts of both.
Until recently, it was thought that muscle fibers could not change from one type to another. Therefore, the average person would have a difficult time becoming an Olympic caliber athlete. However, new research shows evidence of muscle fibers changing from one type to another. (1) This research suggests that fiber type can in fact change with a vigorous training schedule. Does this mean that anyone can be an Olympian with the proper training? Probably not, but it does give hope to many people who may be slightly less of a natural athlete than some of their competitors.
The caliber of an Olympic athlete is incomprehensible to most weekend warriors. In order to compete in this elite group of competitors it is difficult to have anything working against you. The evidence shows that all athletes in a given competition share certain physiologic characteristics. It had been thought that in order to be an Olympian, you would have to be born with muscle composition tailored to your event. However, this new research shows that our bodys muscle is adaptable, and can be shaped by proper training. Perhaps there is an Olympian somewhere inside each of us...
(1) Andersen, JL; Schjerling, P; Saltin, B. Scientific American. "Muscle, Genes and Athletic Performance" 9/2000. Pages 48-55