Kelly was in charge of conducting tests at the Fight Science studio and supplied the project with a $150,000 (U.S.) government-certified crash-test dummy.
"The dummy used for the experiment was one typically used in the automotive industry," Kelly said.
"We took the dummy and put in sensors that would be more appropriate for the application of martial artists."
These so-called load-cell sensors were placed in strategic areas on the dummy, such as the upper neck, lower neck, chest, and knee.
Another device called a potentiometer was placed in the dummy's chest to measure displacement caused by a frontal strike.
The fighters themselves were fitted with reflective markers and sensors in their shoes that allowed scientists to track and create computer animations of how the body generates each attack.
More Powerful Than a Sledgehammer
In one experiment, experts in karate, boxing, kung fu, and tae kwon do all took turns striking the dummy in the face.
The researchers were surprised to find that boxing is the fighting style capable of delivering the most force in a single punch.
Boxer Steve Petramale delivered about 1,000 pounds (453.6 kilograms) of impact force, the equivalent of swinging a sledgehammer into someone's face.
His punch, the sensors revealed, starts in the feet and travels up the legs through the hips to the chest and shoulders, multiplying in force as it travels up the body.
(See photo stills and computer images of the fighters from Fight Science.)
Strong as a Car Crash
But martial artists are perhaps best known for being able to deliver devastating kicks.
To test this power, Kelly had the participants use their unique styles to land kicks on the dummy's chest.
The tae kwon do spinning back kick delivered more than 1,500 pounds (680.4 kilograms) of force, while the kung fu flying double kick produced about 1,000 pounds (453.6 kilograms) of force.
But the undisputed winner practices a discipline known for its ability to deliver a knockout: Muay Thai, also known as Thai boxing.
(Related news: "Thai 'Ladyboy' Kickboxer Is Gender-Bending Knockout" [March 2004].)
Melchor Menor, a former two-time Muay Thai world champion, uses a simple technique to incapacitate his opponents: a knee to the chest at close quarters.
Menor himself was surprised at how powerful this move can be.
"I wasn't expecting to have the highest force. When he said the power of the knee [kick] was equal to the power of a 35-mile-an-hour [56.3-kilometer-an-hour] car crash, it was humbling."
The displacement sensor in the dummy's chest measured nearly two inches (five centimeters) of chest compression from Menor's knee strike.
Like the boxer's punch, the energy from this kick starts from the feet and moves up to the knee. The blow is delivered to the soft tissue below the rib cage while Menor holds his opponent's head stationary.
The ribs are driven backward through the lungs and solar plexus, a cluster of nerve cells behind the human stomach that controls some organ functions.
Truly a death blow, Menor's knee kick can cause internal bleeding and even cardiac arrest.
Faster Than a Snake
According to an old legend, martial artists should strike with the speed of a snake.
But at an average of eight to ten feet (two-and-a-half to three meters) a second, a snake strike would seem beyond the reach of even the fastest fighter.
As it turns out, a kung fu punch can give even the fastest snake a run for its money (related: see videos, photos, and news articles about the real-life abilities of snakes).
Alex Huynh is a three-time gold medalist in wushu, a style of kung fu. He's also made in his mark in Hollywood as a stunt double in movies like Pirates of the Caribbean.
For the experiment Huynh's strikes were measured by an instrument called an accelerometer.
The results of the test showed an astonishing speed of more than 40 feet (12.2 meters) a second.
"We martial artists knew we had the ability to hit hard and fast, but I never thought I could hit four times faster than a snake," Huynh said.
Huynh is also quick to point out that no one style is best.
"As the show demonstrates, each individual school has strengths," he said. "The goal is to find one that is the best for you."
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