Study: For Athletes, It's Speed or EnduranceNot Both
Bijal P. Trivedi
|February 13, 2002|
A team of researchers in Belgium has analyzed the performances of 600
world class decathletes and found biological evidence to support the old
adage: A jack of all trades is master of none.
found that athletes who excelled in one event in the decathlon tended to
rank lower than average in the other nine events.
Biologists have long assumed that there are evolutionary constraints on locomotive systemsanimals that are good at sprinting tend to have low endurance. But this cost, or trade-off, between speed and endurance has been difficult to prove, said Australian Robbie Wilson, of the University of Antwerp.
The classic example of the trade-off can be seen in the cheetah. The cheetah is the fastest sprinter on the planet but can sustain the activity only for very short periods.
But finding other examples in nature is tough because many factors mask these trade-offs.
Wilson's team analyzed decathlon results for 600 athletes and found that trade-offs were reflected in the performances.
After using statistical tools to remove masking factors Wilson found that athletes who performed well in an event like the 100-meter sprint also did well in the long jump, the 400-meter, and the 110-meter hurdles. These are all events that require short, explosive bursts of energy. However, these athletes did poorly in the high-endurance 1,500-meter event.
A similar trade-off was seen in athletes who performed well in the shot put, which demands tremendous upper body strength, but displayed a poor-to-average performance in the 1,500-meterswhich requires strength and endurance in the lower limbs.
Wilson's study is published in the February 14 issue of the journal Nature.
Wilson is interested in the physiological basis behind these trade-offshow the overall body shape and muscle types affect an animal's speed and endurance. "Fast muscle fibers," or white muscle, produce high levels of power for short periods. "Slow muscle fibers," or red muscle, produce less power but for longer periods. Wilson believes that the proportion of each muscle type may partly influence whether an animal is a sprinter or a long-distance runner.
Trade-offs are Inevitable
"If you stand a sprinter next to a marathon runner, there is a massive difference in the shapes of the two athletes," said Wilson.
If you were going to design a human and make him as strong and powerful as possible, the person might be eight feet (2.5 meters) tall and have a very muscular and bulky body. But the strength resulting from this design would come at the cost of maneuverability.
"You can't have both," said Wilson. A human designed for speed would be small and lean and have a much lower center of gravity.
Wilson and his colleagues also found proof to support the old truism: "A jack of all trades is master of none." This statement is ultimately about trade-offs, said Wilson.
Wilson found that athletes who were outstanding in one event performed relatively poorly in the others. By contrast, a decathlon champion was a "jack" of all ten events.
"The champs didn't stand out in any event," he added.
"Animals are specialized for a specific task at the cost of another." Wilson has found, from studies comparing 12 species of lizard from Greece and Croatia, that those species with speed lacked endurance.
Wilson and his colleagues will analyze the results of heptathlons (seven events) to determine whether female athletes display similar trade-offs.
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