for National Geographic News
For an Olympian athlete looking to out-jump the competition, clutching a hefty mass of lead or stone in each hand sounds like the last thing that would help. But that's exactly what ancient Greek long-jumpers did. Vases from the period show athletes holding pairs of matching weights, which the Greeks called "halteres."
Now, a pair of biomechanics researchers has offered a scientific explanation of how this counterintuitive tactic worked.
They solved the mystery with the aid of computers and high-tech equipment designed to measure force and motion, but they also readily acknowledged the contributions of a distant intellectual predecessor: "Amazingly enough, Aristotle was very close to the solution," said Italian researcher Alberto Minetti, a professor of sports science at Manchester Metropolitan University in Alsager, England.
Using a computer code written to model the mechanics of jumping, Minetti and graduate student Luca Ardigó studied how halteres could affect the leaps of standing long-jumpers. The researchers then asked volunteers to put the virtual experiments to the test by jumping from a standstill either unencumbered or holding weights of varying masses.
In both experiments, Minetti said, "we found three kilograms [6.6 pounds] was the optimum mass" to carry in each hand.
The ancient athletes apparently determined this for themselves, presumably from trial and error.
"This is the average mass of the halteres that [archaeologists] have found," Minetti noted.
Actual specimens vary from 2.4 to 9.9 pounds (1.1 to 4.5 kilograms) each. Optimal weight would have varied slightly depending on an individual jumper's height and arm length.
Above the Competition
Using halteres enabled standing long-jumpers to exploit several properties of physics, the researchers determined.
First, by swinging their artificially heavy arms forward and above their heads just before launching themselves into the air, jumpers could shift their weight both upward, as though jumping from a platform, and forwardeffectively starting in front of the starting line. These tactics depend on shifting the center of mass, the theoretical balancing point on a jumper's body.
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