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HuffPo: Cheating in Sports — Where Do We Go From Here?

Definitions and standards for what constitutes cheating vs. fairness have never been so needed or consequential. — Weyand

2015-09-13-1442168688-1501438-HuffPoFairnessFinalpic-thumb

SMU physiologist and biomechanics researcher Peter G. Weyand contributed a piece on cheating in sports to the U.S. online news magazine and blog the Huffington Post.

The piece addresses how modern cheating controversies in sports indicate the need for a new approach to judge fairness that encompasses a broader range of possibilities.

Weyand leads the SMU Locomotor Performance Laboratory and is recognized worldwide as an expert in human running performance.

An expert in the locomotion of humans and other terrestrial animals, Weyand’s broad research interests focus on the relationships between muscle function, metabolic energy expenditure, whole body mechanics and performance.

Weyand’s Huffington Post article, “Cheating in Sports — Where Do We Go From Here?” published Sept. 14, 2015.

EXCERPT:

By Peter Weyand
in the Huffington Post

“I can’t define it, but I know it when I see it.” — U.S. Supreme Court Chief Justice Potter Stewart on pornography in Jacobellis v. Ohio, 1964

Consider some of the current controversies in organized sport: football inflation pressures, “flopping” and “diving” to deceive basketball and soccer officials, performance-enhancing drug (PEDs) cases, possible techno-doping via streamlined suits and artificial limbs, and the potential for genetic doping.

These and other contemporary issues pose unprecedented challenges to the integrity of organized sport. Accordingly, definitions and standards for what constitutes cheating vs. fairness have never been so needed or consequential.

History provides us with clear instances of cheating in sport: Chicago’s “Black Sox” conspiring to intentionally lose baseball games in the 1919 World Series, pitcher Gaylord Perry throwing spitballs in the 1970s, or sprinter Ben Johnson taking banned steroids leading into the 1988 Olympics.

However, many contemporary sport “cheating” controversies simply cannot be evaluated in an equivalently black and white framework.

Consider the ethical dilemmas the following situations pose for modern athletes and athletics: Is it cheating to take a new “designer drug” if: a) it is not banned, b) it enhances performance, and c) many of your competitors take it, and d) you are disadvantaged if you do not?

Is it cheating to fake a fall to induce a referee to call a foul on an opponent?

Is it cheating for an athlete seeking enhanced endurance to sleep in an altitude tent to boost red blood cell production when: a) the practice is not illegal, and b) other athletes do not have the means to do the same.

Is it cheating to use genetic techniques (rather than physical training) to activate dormant portions of one’s DNA to improve muscle performance?

Three of the preceding scenarios presented themselves years ago, the fourth may or may not have yet occurred, but has been a credible threat for some time. All four pose major challenges to the health and integrity of sport.

Yet, while the integrity of sport depends on fairness, the commitment needed to provide it in a viable contemporary form does not seem to be in place. Hence, what is perhaps the greatest threat to both the integrity and health of modern sport – an onslaught of sophisticated techniques to gain advantage by any means possible – is under-recognized, under-resourced and inadequately addressed.

Even a cursory look at the problem makes clear that performance enhancement techniques have raced ahead while standards and policies have not. Athletes and coaches have acknowledged and openly complained that outcomes are unfairly determined by technology rather than ability. Leagues have implemented new policies only to quickly acknowledge they fail to remedy the fairness problems they address (see the NBA’s flopping fines). Instructional videos for inducing foul calls on opponents have been published featuring leading players. “Dirty” athletes, like Lance Armstrong, pass hundreds of doping tests while “clean” athletes are implicated.

Read the full article.

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SMU is a nationally ranked private university in Dallas founded 100 years ago. Today, SMU enrolls nearly 11,000 students who benefit from the academic opportunities and international reach of seven degree-granting schools. For more information see www.smu.edu.

SMU has an uplink facility located on campus for live TV, radio, or online interviews. To speak with an SMU expert or book an SMU guest in the studio, call SMU News & Communications at 214-768-7650.

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Wall Street Journal: March’s True Madness — Flopping

As in the NBA, the art of embellishing contact has become widespread in college basketball

Peter Weyand, flopping, Mark Cuban, NCAA

As the 2015 NCAA tournament gets into gear, Wall Street Journal sports reporter Brian Costa quoted SMU locomotor expert Peter Weyand for an article on flopping among college basketball athletes.

The article, “March’s True Madness: Flopping,” quotes Weyand and other experts on the prevalence of flopping in college basketball and the ability of referees to detect it.

The article published March 17, 2015.

Read the full story.

EXCERPT:

By Brian Costa
Wall Street Journal

At some point during every NCAA tournament game, a player with the ball will bump into a defender. The defender will fall to the floor, seemingly blown backward by the overwhelming force of his opponent. And referees will be faced with a question that is becoming increasingly difficult to answer: Was it a foul or a flop?

Mimicking the NBA, where the practice has become widespread, college players are becoming ever more proficient in the art of flopping—embellishing or outright faking blows to their bodies to convince referees to call a foul.

The most flagrant histrionics have attracted widespread attention. In February, a video clip of St. John’s swingman Sir’Dominic Pointer flailing his arms in an apocalyptic tumble became a viral hit. But the savviest actors aren’t nearly as obvious about it.

“I’ve had countless games this year where you say, ‘That’s a flop,’ ” ESPN analyst Jay Bilas said. “There’s no way that amount of force caused that amount of physical reaction from the defender. You’d have to be shot in the chest with a bazooka to fall like that.”

Although the frequency of such plays is unclear—the NCAA doesn’t track offensive fouls—the powers that be in college basketball believe there is a problem. Belmont coach Rick Byrd, who chairs the NCAA men’s basketball rules committee, said flopping is becoming prevalent enough that he wants to address it at the committee’s next meeting in May. And it isn’t only happening with players trying to draw a charge. [….]

[….]Part of the issue for any league is the uncertainty surrounding an essential question: what amount of physical reaction should be expected on a given play?

“How much force does it really take in a typical basketball encounter to knock someone off balance?” said Peter Weyand, a physiologist and biomechanist at Southern Methodist University. “That information is not out there.”

With funding from Dallas Mavericks owner Mark Cuban, Weyand is leading a study to find out. Using people of various heights and weights, the study simulated typical basketball collisions and measured both the forces involved and the subjects’ natural reactions.

Read the full story.

Follow SMUResearch.com on twitter at @smuresearch.

SMU is a nationally ranked private university in Dallas founded 100 years ago. Today, SMU enrolls nearly 11,000 students who benefit from the academic opportunities and international reach of seven degree-granting schools. For more information see www.smu.edu.

SMU has an uplink facility located on campus for live TV, radio, or online interviews. To speak with an SMU expert or book an SMU guest in the studio, call SMU News & Communications at 214-768-7650.

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The New York Times: The Fast Life of Oscar Pistorius

The New York Times has written a comprehensive piece on the long-running global controversy surrounding double-amputee runner Oscar Pistorius, the South African vying to compete in the Olympics.

The Jan. 18 article, “The Fast Life of Oscar Pistorius,” cites extensively the work of SMU’s Peter Weyand, an expert in human locomotion. Controversy has swirled around Pistorius as the debate continues over the scientific advantage he enjoys as a result of his high-tech, carbon fiber artificial legs. Weyand helped lead a team of scientists who are experts in biomechanics and physiology in conducting experiments on Pistorius and the mechanics of his racing ability.

Weyand is widely quoted in the press for his expertise on human speed. He is an SMU associate professor of applied physiology and biomechanics in the Annette Caldwell Simmons School of Education & Human Development.

Read the full story.

EXCERPT:

By Michael Sokolove
The New York Times

Oscar Pistorius trains inside a converted garage at the home of his personal trainer, a former professional rugby player. Iron pull-up bars and a variety of ropes and pulleys are bolted to brick walls. Free weights are lined up on the floor, along with hammered-together wooden boxes that serve as platforms for step-ups and standing jumps. Some of the equipment is clamped to an exterior wall of the garage, opposite an uncovered patio; when it rains, athletes just carry on and get soaked. “It’s old-school,” Pistorius said as we drove up to the place early one morning. “Some of the guys who train here, they bang it so hard, they often get sick in the garden. Nobody judges them.” [ … ]

[ … ] Since the initial paper was published, Weyand has been vocal in stating that Pistorius is at an advantage, a substantial one. The reasons he puts forward were not part of the rationale behind the I.A.A.F.’s disqualification of Pistorius — in effect, not among the “charges” against him — so Pistorius’s legal and scientific team did not have to disprove them at his appeal. The basis of the argument made by Weyand is not hard to follow: The Cheetah blade and its hardware are light, about 5.4 pounds as opposed to the weight of an intact leg and foot for someone of Pistorius’s build, about 12.6 pounds. As a result, his “swing times” — how quickly he can reposition his limbs — are unnaturally fast, “quite literally off the biological charts,” as Weyand (who did not testify in Lausanne) put it in a point-counterpoint debate with Herr in The Journal of Applied Physiology.

Weyand and a colleague, Matthew Bundle of the University of Montana (one of the seven authors listed on the initial journal article), expanded on this last year. “Mr. Pistorius can reposition his lightweight, artificial limbs in 0.28 seconds, and therefore 20 percent more rapidly than most intact-limb athletes,” they wrote. “To appreciate just how artificial Mr. Pistorius’s swing time is, consider that the average limb-repositioning time of five former 100-meter world-record holders (Ben Johnson, Carl Lewis, Maurice Greene, Tim Montgomery and Justin Gatlin) is 0.34 seconds. Mr. Pistorius’s limb-repositioning times are 15.7 percent more brief than five of the fastest male sprinters in recorded human history.”

The most provocative aspect of Weyand and Bundle’s argument — and clearly the biggest affront to Pistorius — is their calculation that the Cheetah blades, over the length of 400 meters, or once around the track, give him an 11.9-second advantage. That would make him no better than an average high school runner. Herr has dismissed this as a “back of the envelope” calculation, and in his contribution to the point-counterpoint, signed by four other authors of the initial paper, asked: “Would Weyand and Bundle predict that the world-record holder, Michael Johnson, would run 31s if he had both legs amputated?” [ … ]

Read the full story.

SMU is a nationally ranked private university in Dallas founded 100 years ago. Today, SMU enrolls nearly 11,000 students who benefit from the academic opportunities and international reach of seven degree-granting schools. For more information see www.smu.edu.

SMU has an uplink facility located on campus for live TV, radio, or online interviews. To speak with an SMU expert or book an SMU guest in the studio, call SMU News & Communications at 214-768-7650.

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Science of Sport: Oscar Pistorius’ controversy continues to bubble

The popular blog The Science of Sport has posted a year-end piece on the long-running global controversy surrounding double-amputee runner Oscar Pistorius, the South African vying to compete in the Olympics.

The blog article cites extensively the work of SMU’s Peter Weyand, an expert in human locomotion. Controversy has swirled around Pistorius as the debate continues over the scientific advantage he enjoys as a result of the high-tech, carbon fiber artificial legs he relies on. Weyand helped lead a team of scientists who are experts in biomechanics and physiology in conducting experiments on Pistorius and the mechanics of his racing ability.

Weyand is widely quoted in the press for his expertise on human speed. He is an SMU associate professor of applied physiology and biomechanics in the Annette Caldwell Simmons School of Education & Human Development.

Read the full blog post.

EXCERPT:

By Ross Tucker
The Science of Sport

[ … ] But 18 months later, an extra-ordinary announcement followed. It was made by Peter Weyand and Matthew Bundle, TWO of the group of six scientists in the Pistorius research team. They came out in November 2009 with the statement that “Pistorius enjoys a large advantage”, and that “we knew it all along”.

This remarkable statement was followed by a point-counterpoint debate in the Journal of Applied Physiology, which revealed a split among those six scientists. It transpired that on the very first day of testing, Weyand (the world’s leading authority on sprint mechanics) and Bundle noted that Pistorius’ mechanics were “off the charts”.

Specifically, his lighter carbon fiber prosthetic blades enabled him to accelerate his limbs so rapidly that he could do what no other runner could in terms of repositioning his limbs.

Weyand had previously established that a limit to sprinting, regardless of speed, was the ability to reposition the limbs, and Pistorius “broke” the limit considerably. That led Weyand to recognize the performance advantage. Weyand and Bundle describe this in their own words:

“Reduced limb repositioning times allow Mr. Pistorius to spend less time in the air between steps. Shorter aerial periods, in turn, substantially reduce how hard Mr. Pistorius must hit the ground during each stance period to lift and move his body forward into the next step.

In this sense, the level of sprinting athleticism required for Mr. Pistorius to achieve world class speeds is dramatically reduced compared to his intact limb competitors. Mr. Pistorius attains world-class sprinting speeds with the ground forces and foot-ground contact times of a slow and relatively uncompetitive runner. Mr. Pistorius’ intact-limb competitors, with natural limb weights and swing times, lack this option, and therefore must achieve their speeds via exclusively biological means. Mr. Pistorius, in contrast, achieves these speeds through the use of technology.”

You can read more about this discovery and the basis for the 12-second advantage they calculated (an overestimate in my opinion) in the detailed article on this site written in August.

Weyand and Bundle speak
The above statements come from a piece that was written by Weyand and Bundle in response to articles I wrote on this site in August. They contacted me to request a one-time post on The Science of Sport, and I was very happy to oblige. However, for various reasons, the posts didn’t happen here, but they were published on the SMU website. I would highly encourage you to read them – they are lucid, to the point, and they clear up many of the misconceptions that you’d have read in the popular media as a result of lies told by Pistorius, Hugh Herr and co.

Read the full blog post

SMU is a nationally ranked private university in Dallas founded 100 years ago. Today, SMU enrolls nearly 11,000 students who benefit from the academic opportunities and international reach of seven degree-granting schools. For more information see www.smu.edu.

SMU has an uplink facility located on campus for live TV, radio, or online interviews. To speak with an SMU expert or book an SMU guest in the studio, call SMU News & Communications at 214-768-7650.

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The Telegraph: The Pistorius problem – how South African blade runner’s artificial legs make him 10 seconds quicker

Australia’s The Telegraph newspaper quotes SMU’s Peter Weyand, an expert in human locomotion, in an Aug. 11 article “The Pistorius problem – how South African blade runner’s artificial legs make him 10 seconds quicker

The Telegraph article examines the controversy surrounding double-amputee sprinter Oscar Pistorius and his qualification for the 2012 London Olympics. What if the 24-year-old South African — the world’s only sprinter with no legs — comes out a winner? Will their be an outcry against Pistorius controversial carbon-fiber prosthetic legs that attach just below his knees?

Weyand is widely quoted in the press for his expertise on human speed. He led a team of scientists who are experts in biomechanics and physiology in conducting experiments on Oscar Pistorius and the mechanics of his racing ability. Pistorius has made headlines worldwide trying to qualify for races against runners with intact limbs, including the Olympics.

Weyand is an SMU associate professor of applied physiology and biomechanics in the Annette Caldwell Simmons School of Education & Human Development.

Read the full story.

EXCERPT:

By Mike Hurst
The Telegraph

When it comes to Blade Runner Oscar Pistorius, the athletics world remains split — science isn’t so indecisive.

Oscar Pistorius, that running paradox — a sprinter without legs — advanced one more step towards fulfilling his dream of competing in the Olympic Games when he was named in South Africa’s 26-member team this week to compete later this month at the world athletics championships in Daegu, South Korea.

His official notification comes after he clocked 400m in 45.07sec last month in Italy to better the International Association of Athletics Federations’ tough qualifying standard of 45.25sec — a time no Australian has recorded this year.

In fact, at the previous world champs two years ago in Berlin, Trinidad’s Renny Quow won the bronze medal with 45.02. In a quiet season for the men’s 400m if Pistorius could replicate his 45.07 in consecutive rounds he could well end up on the medals podium.

But then what? Will there be an outcry from those able-bodied sprinters who could not run fast enough to beat Pistorius? Will they campaign to the IAAF against the Pistorius appliances — the carbon-fibre J-shaped blades he wears in place of his legs which were amputated below the knee before his first birthday?

What might the IAAF, the custodians of the major Olympic sport of track and field, do next? Would they dare try again to ban him from competing in London next year?

The IAAF have tried once and failed to ban the technology that enables Pistorius to engage in his flight of fancy to run in the Olympics.

Pistorius took the IAAF to the Court of Arbitration for Sport in 2008. His lawyers cited the opinion of seven scientists (6 American and one French) that the evidentiary basis of the IAAF eligibility ban was not sound. The CAS primarily considered the research conducted on behalf of the IAAF by Professor Peter Bruggemann of Cologne sports university which was used to provide the rationale for the IAAF’s eligibility ban.

In fact both scientific parties found that Pistorius enjoys a big advantage over athletes with biological legs but crucially, in its own narrow terms of reference for the case, CAS questioned whether Prof Bruggemann’s findings adequately supported the IAAF claims and the eligibility ban.

The CAS ruled that the evidence the IAAF offered did not adequately support the eligibility ban on Pistorius and overturned it.

The IAAF could well have restated their case against Pistorius but with public opinion, including the support of many of his fellow sprinters, strongly in favour of the courageous and persistent Paralympian they decided not to go on with the matter.

The IAAF’s decision was at least partly taken in the belief that biology would settle the matter and Pistorius might not attain the tough selection time in the first place.

Two of the physiology professors whose research was sought by Pistorius’s legal team, Peter Weyand and Matthew Bundle, told The Daily Telegraph by email yesterday: “We both admire the inspiring performances of Oscar Pistorius.

“We greatly respect the dedication and persistence he has exhibited in his successful quest to qualify for the World Track and Field Championships and congratulate him on his historic accomplishment.

Read the full story.

SMU is a nationally ranked private university in Dallas founded 100 years ago. Today, SMU enrolls nearly 11,000 students who benefit from the academic opportunities and international reach of seven degree-granting schools. For more information see www.smu.edu.

SMU has an uplink facility located on campus for live TV, radio, or online interviews. To speak with an SMU expert or book an SMU guest in the studio, call SMU News & Communications at 214-768-7650.

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National Post: Five things: The trials and tribulations of Oscar ‘Blade Runner’ Pistorius

Canada’s National Post newspaper quotes SMU’s Peter Weyand, an expert in human locomotion, in an Aug. 8 article “Five things: The trials and tribulations of Oscar ‘Blade Runner’ Pistorius

The Post article examines the controversy surrounding double-amputee sprinter Oscar Pistorius. Preparing now for the 2012 London Olympics, the 24-year-old South African once again is under the spotlight for his controversial carbon-fiber prosthetic legs that attach just below his knees.

Weyand is widely quoted in the press for his expertise on human speed. He led a team of scientists who are experts in biomechanics and physiology in conducting experiments on Oscar Pistorius and the mechanics of his racing ability. Pistorius has made headlines worldwide trying to qualify for races against runners with intact limbs, including the Olympics.

Weyand is an SMU associate professor of applied physiology and biomechanics in the Annette Caldwell Simmons School of Education & Human Development.

Read the full story.

EXCERPT:

National Post
South African double amputee Oscar Pistorius was chosen to run in the 400 metres and 4x400m relay at the world athletics championships later this month. Here are five things to know before the big race in Daegu, South Korea.

1. His legs are better than your legs
Known as the ‘Blade Runner’ and the ‘Fastest man with no legs,’ Pistorius had both legs amputated below the knee for medical reasons when he was 11 months old.

He uses high-tech carbon-fibre blades in competition, with spikes on the forefoot for the track. The International Association of Athletics Federations (IAAF) began to monitor his races in the 2007 to analyze his technique and determine if he had an advantage.

“The company does make bionic feet that have hydraulics and are battery powered but this is a passive foot,” Pistorius told the Daily Telegraph in 2007. “That means that the output energy is not as much as the input energy so it definitely does not give me an unfair advantage.”

2. But they don’t come cheap
In a 2007 Wired feature on Pistorius’ attempt to qualify for the 2008 Olympics, the magazine says each leg costs between $15,000 (US) and $18,000 (US). It’s a small price to pay for an Olympic dream, considering the custom-made Cheetah Flex-Foot blades are made to look like human legs.

It also explains why Pistorius insists on taking the prosthetic legs in his carry-on luggage when he flies, especially after one incident in the United States. “I went to run in Atlanta and my legs ended up in Salt Lake City,” he tells the Telegraph.

3. He’s had trouble with the IAAF
Pistorius first competed against able-bodied athletes in 2007 but the IAAF then amended its rules to ban the use of “any technical device that incorporates springs, wheels or any other element that provides a user with an advantage over another athlete not using such a device.”

In the following year the world governing body said scientific research had shown Pistorius enjoyed an advantage over able-bodied athletes and banned him from competitions held under their rules.

However, the decision was overruled by the Court of Arbitration for Sport, making Pistorius eligible for the 2008 Beijing although he was unable to qualify for the South African team, winning gold medals instead in the Paralympic 100, 200 and 400 meters.

4. And then there’s the ’10-second advantage’
The question of whether Mr. Pistorius’ artificial limbs artificially enhance his running speeds is a matter of scientific disagreement. Two researchers who studied Pistorius, Drs. Matthew Bundle and Peter Weyand, conclude that his artificial limbs enhance his sprint running performances by 15-30% over his intact limb competitors. Their findings were published in the Journal of Applied Physiology in 2009.

Read the full story.

SMU is a nationally ranked private university in Dallas founded 100 years ago. Today, SMU enrolls nearly 11,000 students who benefit from the academic opportunities and international reach of seven degree-granting schools. For more information see www.smu.edu.

SMU has an uplink facility located on campus for live TV, radio, or online interviews. To speak with an SMU expert or book an SMU guest in the studio, call SMU News & Communications at 214-768-7650.

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New York Times: As Debate Goes On, Amputee Will Break Barrier

The New York Times tapped the expertise of SMU’s Peter Weyand, an expert in human locomotion, in an Aug. 8 article “As Debate Goes On, Amputee Will Break Barrier

Journalist Juliet Macur examines the controversy surrounding double-amputee sprinter Oscar Pistorius. Preparing now for the 2012 London Olympics, the 24-year-old South African once again is under the spotlight for his controversial carbon-fiber prosthetic legs that attach just below his knees.

Weyand is widely quoted in the press for his expertise on human speed. He led a team of scientists who are experts in biomechanics and physiology in conducting experiments on Oscar Pistorius and the mechanics of his racing ability. Pistorius has made headlines worldwide trying to qualify for races against runners with intact limbs, including the Olympics.

Weyand is an SMU associate professor of applied physiology and biomechanics in the Annette Caldwell Simmons School of Education & Human Development.

Read the full story.

EXCERPT:

By Juliet Macur
The New York Times

The moment that the sprinter Oscar Pistorius had hoped for and trained for finally came Monday when he was named to South Africa’s team for the track and field world championships, which will make him the first amputee to compete at the event.

“If I manage to make it through the heats, I would be thrilled.” Oscar Pistorius, on qualifying for the world championships.

Pistorius, a four-time Paralympic champion, will race in the 400 meters and the 4×400 relay against men who have two natural legs, while he uses prosthetics. Last month, he ran fast enough to meet the Olympic qualifying standard, and now he will blaze a trail.

“This will be the highest-profile and most prestigious able-bodied event which I have ever competed in, and I will face the highest caliber of athletes from across the planet,” Pistorius, 24, said in a statement sent Monday by his agent, Peet van Zyl. “If I manage to make it through the heats, I would be thrilled.”

The road to the world championships could just lead to a berth in the 2012 London Games for Pistorius, who said he had never considered himself disabled and had never considered the world championships or Olympics out of his reach.

Even so, that road to making the team for this month’s world championships, which will begin Aug. 27 in Daegu, South Korea, has not been smooth for Pistorius — and his road to the Olympics may not be any smoother.

Born without his fibulas, the long bones that span from the knees to the ankles, Pistorius relies on carbon-fiber prosthetic limbs to propel him around the track in times comparable to some of the world’s top runners. And therein remains the question that has been the crux of a continuing debate: do those high-tech legs give him an unfair advantage?

In 2008, the International Association of Athletics Federations, track and field’s governing body, thought so. It ruled that Pistorius was ineligible to compete in the worlds because his prosthetic legs made it easier for him to run than competitors with legs made of flesh and bone. But he appealed to the Court of Arbitration for Sport and won in May 2008.

The court, though, provided no definitive answer to the underlying question of whether Pistorius was naturally fast or just fast because of his prosthetic legs. It said that the I.A.A.F. failed to meet its burden of proving that Pistorius’s legs provided him with an overall advantage or disadvantage.

To further complicate the issue, the court made it clear that the case could be reopened, saying that advances in technology and a different testing regime might prove that Pistorious’s legs did, in fact, give him an edge.

“There was a disagreement among the scientists, but I feel that the conclusion was overwhelming that he’s a lot faster with the legs than someone is without them,” said Peter Weyand, an associate professor of applied physiology and biomechanics at Southern Methodist University and one of seven scientists who in 2008 conducted physiological and biomechanical tests on Pistorius at Rice University.

Read the full story.

SMU is a nationally ranked private university in Dallas founded 100 years ago. Today, SMU enrolls nearly 11,000 students who benefit from the academic opportunities and international reach of seven degree-granting schools. For more information see www.smu.edu.

SMU has an uplink facility located on campus for live TV, radio, or online interviews. To speak with an SMU expert or book an SMU guest in the studio, call SMU News & Communications at 214-768-7650.

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ESPN: The Olympics loom for Oscar Pistorius

Sports journalist Johnette Howard quotes SMU’s Peter Weyand, an expert in human locomotion, in an Aug. 5 article “The Olympics loom for Oscar Pistorius

Howard examines the accomplishments of double-amputee sprinter Oscar Pistorius and the controversy that has dogged his racing career. Preparing now for the 2012 London Olympics, the 24-year-old South African once again is under the spotlight for his controversial carbon-fiber prosthetic legs that attach just below his knees.

Weyand is widely quoted in the press for his expertise on human speed. He led a team of scientists who are experts in biomechanics and physiology in conducting experiments on Oscar Pistorius and the mechanics of his racing ability. Pistorius has made headlines worldwide trying to qualify for races against runners with intact limbs, including the Olympics.

Weyand is an SMU associate professor of applied physiology and biomechanics in the Annette Caldwell Simmons School of Education & Human Development.

Read the full story.

EXCERPT:

By Johnette Howard
ESPN

You hope the murmuring and arguing that has already restarted now that Oscar Pistorius has done the remarkable, the extraordinary, the heretofore unfathomable will not drag him down between now and the 2012 London Olympics. Because what Pistorius, a double-amputee sprinter, was able to do on a muggy night in Lignano, Italy, on July 19 is the sort of mind-blowing achievement that shouldn’t be unfairly derailed by this unsettled debate. He thought he had already navigated it once, but now it’s likely to trail the 24-year-old South African all the way to next year’s Olympic Summer Games. [ … ]

Perhaps the most contentious assertion, Peter Weyand, an associate professor of applied physiology and biomechanics at Southern Methodist University, and Matthew Bundle, now an assistant professor at the University of Montana, have argued that, among other things, Pistorius enjoys as much as a 10 to 12 second advantage in a 400-meter race using his prosthetic legs, for reasons Weyand says have to do with the frequency of how quickly Pistorius is able reposition his lightweight legs as he strides; the force he exerts; the longer length of time each of his prosthetic feet remains on the ground; and reduced ground force requirements to attain the same sprinting speeds.

“You can collect more data, but the answers about Oscar Pistorius are in, in my opinion,” Weyand said in a phone interview Tuesday. “He is able to run faster than many of his competitors even though he does not hit the ground as hard.”

To which Hugh Herr of MIT, another member of the Pistorius research group, retorts, “It baffles me why Weyand and Bundle continue to say that.”

Herr, an associate professor and director of MIT’s biomechatronics research group, argues, “You really have to have rigorous, peer-reviewed, published, carefully examined scientific evidence. [Weyand-Bundle’s argument] is simply a calculation, nearly a back-of-the-envelope calculation. To label it as a scientific study is very misleading. ??? Their calculation was never published in a peer-reviewed paper. It was in the point/counterpoint article, which was not rigorously peer-reviewed.”

So the debate about Pistorius lives on. But how much does it still matter?

Other than perhaps inhibiting his training — as the IAAF controversy and CAS fight did back in 2008, when he admitted it dragged him down emotionally (“It’s been completely on this kid’s back to prove everything himself so he can run,” Mullins says) — the griping needn’t stop him.

“As far as we are concerned, the CAS decision is final and the case is closed, as long as he continues to compete on the same prosthetic legs the CAS ruled on,” insisted Jeffrey Kessler, the New York-based attorney who took on Pistorius’ case on a pro bono basis and represents the National Basketball Player’s Association and NFL Players Association in their labor negotiations. “I spoke to Oscar on the phone the other day and I’ve committed to him that when he runs in London, I will be there. To me, this is about the rights of the disabled. He is one of the most inspiring people I’ve ever met in my life.”

Weyand has been careful to stress that he admires Pistorius, too, and finds the man and his accomplishments “absolutely extraordinary.” But Weyand considers himself just a scientist doing his job, and added that nothing he has asserted, “should in any way diminish what Oscar has done.”

Read the full story.

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ESPN Grantland: Is the Fastest Human Ever Already Alive?

Sports journalist Chuck Klosterman quotes SMU’s Peter Weyand, an expert in human locomotion, in the July 12 article “Is the Fastest Human Ever Already Alive?

Klosterman looks at the evolution of track’s 100-meter dash and runners’ repeated shattering of the world record for the race. In discussing the mechanics of human speed, he quotes Weyand on how it relates to a runner’s physiology and the force sprinter’s apply to the ground.

Weyand, who is widely quoted in the press for his expertise on human speed, is an SMU associate professor of applied physiology and biomechanics in the Annette Caldwell Simmons School of Education & Human Development.

He led a team of experts in biomechanics and physiology that conducted experiments on Oscar Pistorius, a South African bilateral amputee track athlete. Pistorius has made headlines trying to qualify for races against runners with intact limbs, including the Olympics.

Read the full story.

EXCERPT:

By Chuck Klosterman
ESPN Grantland

Allow me to spare you the hyperbole: Usain Bolt is fast.

He is, as far as we can tell, the fastest human who’s ever lived — in 2009, at a race in Berlin, he ran the 100-meter dash is 9.58 seconds. This translates to an average speed of just over 23 mph (with a top speed closer to 30 mph). His ’09 performance in Germany was .11 quicker than the 9.69 he ran at the 2008 Beijing Olympics, the fattest chunk ever taken off a world record at that distance. Considering the unadulterated simplicity of his vocation and the historic magnitude of his dominance, it’s easy to argue that Bolt has been the world’s greatest athlete of the past five years. And yet there’s an even easier argument to make than that one: Within the next 10 years, Bolt’s achievements as a sprinter will be completely annihilated.

This is not guaranteed, of course, but it’s certainly more plausible than speculative — for the past 30 years, the men’s record in the 100-meter dash has been assaulted so continually that many of its former record holders don’t even qualify as difficult answers to trivia questions. This was not always the case: Jim Hines broke the 10.0 barrier with a 9.95 at the (high-altitude) 1968 Olympics; that mark stood for 15 years before Calvin Smith ran a 9.93 (also at altitude) in Colorado Springs. But since 1983, the record has been shattered more than a dozen times. Ben Johnson’s steroid-fueled 9.83 in ’87 was the first massive blow, but eight others have chipped away at the record with increasing regularity (Bolt just happened to use a sledge hammer). …

… “The scientific understanding of sprinting is pretty immature,” concedes Peter Weyand, and — since Weyand has become the de facto American expert on the science of sprinting — that tells you just how mysterious this phenomenon is. A physiologist and biomechanist at Southern Methodist University, Weyand specializes in terrestrial locomotion; while at Harvard in the ’90s, he directed experiments at Concord Field Station, a facility where researchers regularly placed animals such as cheetahs,1 wolverines, and kangaroos on treadmills to understand the mechanics of movement. Now 50, Weyand was also a fairly swift runner in his younger days, having run the 100-yard dash in 10.8 as a high school student. “The one thing about sprinting we all understand is that speed comes from how hard the runner’s foot hits the ground. Someone like Bolt is hitting the ground with 1,000 pounds of force, and we just don’t how he does that. For example, we have a very accurate understanding of how much weight someone can lift — we can take a person’s frame and his muscle mass and accurately estimate how much weight he’ll be able to bench press. But world-class sprinters deliver twice as much force as our estimates indicate, and we don’t know why.”

Read the full story.

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Discovery News: Why walking is harder for smaller people

A Nov. 15 article on Discovery News cites the research of SMU physiologist and biomechanist Peter Weyand in which he and other scientists found that everyone uses about the same amount of energy when they walk, but short people use more energy over a given distance. The reason: people with shorter legs take more steps to cover the same distance as people with longer legs.

Weyand says the study has clinical applications and weight balance applications. In addition, the military is interested too because metabolic rates influence the physiological status of soldiers in the field, he said.

Also covering the research is MSNBC with the story Take that, Stretch! Short people burn more calories walking, and UPI, with its story Equation calculates energy cost of walking.

Weyand is an SMU associate professor of applied physiology and biomechanics in the Annette Caldwell Simmons School of Education & Human Development. He led a team of experts in biomechanics and physiology that conducted experiments on Oscar Pistorius, a South African bilateral amputee track athlete. Pistorius has made headlines trying to qualify for races against runners with intact limbs, including the Olympics.

Excerpt:

By Liz Day
Discovery News

Why do children tire more quickly than adults when out for a walk?

Like most people who have had to carry a tired child home after a long walk, Peter Weyand of Southern Methodist University asked himself that same question. Scientists had long recognized that smaller people use more energy per kilogram body mass than larger individuals when walking.

He wanted to know why.

The reason smaller people use more energy is not due to a different gait or a less efficient metabolic rate per stride. The key was something simpler: their height.

Smaller people tire faster because they take more steps to cover the same distance or travel the same steps as taller people. Their strides are shorter.

Weyand teamed up with three other researchers to study the issue. Their findings are published in the Journal of Experimental Biology.

To test the cost of walking, the team measured the metabolic rates of children and adults. Participants ranged from 5 to 32 years old, from 35 to 195 lbs and from 3’6 to a little over 6 feet tall.

The volunteers were filmed walking on treadmills. Their oxygen consumption and carbon dioxide production were measured to gauge their metabolic rate.

The team compared their walks too — measuring their strides, the way they walked, stride durations and the proportion of each stride spent in contact with the ground.

Results showed everyone moved in the exact same way, no matter if they were 4 feet or 6 feet tall. Analysis also found that everyone used the same amount of energy per stride, regardless of height. So, the energy discrepancy was not due to the style of walking.

Finally, the researchers plotted walkers’ heights against their minimum energy expenditure. The results excited them. The walkers’ energy costs were almost perfectly inversely proportional to their heights. Ergo, tall people walk more economically because they have longer strides and take fewer steps to cover the same distance.

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MSNBC: Take that, Stretch! Short people burn more calories walking

A Nov. 12 article on MSNBC cites the research of SMU physiologist and biomechanist Peter Weyand in which he and other scientists found that everyone uses about the same amount of energy when they walk, but short people use more energy over a given distance. The reason: people with shorter legs take more steps to cover the same distance as people with longer legs.

Weyand says the study has clinical applications and weight balance applications. In addition, the military is interested too because metabolic rates influence the physiological status of soldiers in the field, he said.

Read the full story.

Also covering the research is UPI, with the story Equation calculates energy cost of walking.

Weyand is an SMU associate professor of applied physiology and biomechanics in the Annette Caldwell Simmons School of Education & Human Development. He lead a team of experts in biomechanics and physiology that conducted experiments on Oscar Pistorius, a South African bilateral amputee track athlete. Pistorius has made headlines trying to qualify for races against runners with intact limbs, including the Olympics.

Excerpt:

By Rachel Rettner
MSNBC

Scientists have come up with a new equation to determine how much energy people actually use while walking.

While previous work has conjured many ways to measure the energy cost of walking, the new equation is among the first to account for the impact of body size, taking into account individuals’ height and weight.

The equation has many possible applications. It could be used to design pedometers that, in addition to distance walked, provide an estimate of calories burned, taking into account a person’s body size. The military may also find the equation handy, possibly using it to calculate how much energy soldiers expend — and thus how many calories they will need — while carrying different loads, said study researcher Peter Weyand, of Southern Methodist University in Dallas.

The findings are published today (Nov. 12) in the Journal of Experimental Biology.
Why height and weight matter .

Scientists knew that shorter people, including children, use up more energy per pound of their body mass when walking than taller people, but they didn’t know why.

Read the full story.

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How much energy does it take to walk? New equation is first to calculate cost of walking

Any parent that takes their kid out for a walk knows that children tire more quickly than adults, but why is that? Do kids and small adults walk differently from taller people or do they tire faster for some other reason?

Peter Weyand from Southern Methodist University is fascinated by the effect that body size has on physiological function.

“This goes back to Max Kleiber’s work on resting metabolic rates for different sized animals. He found that the bigger you are the slower each gram of tissue uses energy,” explains Weyand, who adds, “It’s interesting to know how and why metabolism is regulated that way.”

Intrigued by the question of why smaller people use more energy per kilogram body mass than larger individuals when walking, Weyand teamed up with Maurice Puyau and Nancy Butte, from the USDA/ARS Children’s Nutrition Research Center at Baylor College of Medicine, and undergraduate Bethany Smith.

Together they decided to measure the metabolic rates of children and adults, ranging from 5 to 32 years old, weighing between 15.9 kilograms and 88.7 kilograms and ranging in height from 1.07 meters to 1.83 meters, to try to find out why larger people are more economical walkers than smaller people.

Weyand and his colleagues publish their discovery that walkers of all heights use the same amount of energy per stride, making short people less economical because they take more steps. They also derive a fundamental equation to calculate exactly how much energy walkers use with direct applications in all walks of life. The team published its discovery in the article “The mass-specific energy cost of human walking is set by stature” in the current issue of The Journal of Experimental Biology.

First Weyand and colleagues filmed male and female volunteers as they walked on a treadmill at speeds ranging from a slow 0.4 meters per second up to 1.9 meters per second. Meanwhile, they simultaneously measured the walkers’ oxygen consumption and carbon dioxide production rates to obtain their total metabolic rate.

Next the team calculated the amount of energy that each person used for walking by subtracting the basal metabolic rate (energy required to maintain the body’s basic metabolic functions) from the total metabolic rate measured while walking. Finally, the team compared the way each person walked, measuring the walkers’ stride lengths, stride durations and the proportion of each stride they spent in contact with the ground (duty factor) to find out if large and small people walk differently.

Analysing the walkers’ styles, the team found that all of them moved in exactly the same way regardless of their height. Essentially, if you scaled a 5 year old up to 2 meters, the giant child would walk in exactly the same way as a 2 meter tall adult. So large people are not more economical because they walk differently from smaller people.

Next the team calculated the metabolic cost of a stride as each walker moved at their most economical pace and they discovered that walkers use the same amount of energy per stride regardless of their height. So, big people do not become more economical because they walk in a more economical style. Something else must account for their increased economy.

Finally, the four scientists plotted the walkers’ heights against their minimum energy expenditure and they were amazed when they got a straight line with a gradient of almost -1. The walkers’ energy costs were inversely proportional to their heights, with tall people walking more economically than short/smaller people because they have longer strides and have to take fewer steps to cover the same distance. So smaller people tire faster because each step costs the same and they have to take more steps to cover the same distance or travel at the same speed.

Based on this discovery the group derived an equation that can be used to calculate the energetic cost of walking.

“The equation allows you to use your height, weight and distance walked to determine how many calories you burn,” says Weyand.

The equation could also be built into popular pedometers to provide users with a more realistic idea of how many calories they expend walking throughout the day. Finally, the team is keen to extend the equation to calculate metabolic costs at any speed.

“This has clinical applications, weight balance applications and the military is interested too because metabolic rates influence the physiological status of soldiers in the field,” explains Weyand. — Kathryn Knight, The Company of Biologists

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Scientific American: Who Will Win: A Squirrel, an Elephant, a Pig or a Safety?

A Nov. 11 article in Scientific American cites the expert analysis of SMU physiologist and biomechanist Peter Weyand as part of an effort to explore the physics of speed and acceleration.

In a special partnership with NBC Learn, the science magazine set up an imaginary 40-yard dash to present additional information for the video series, “The Science of NFL Football.”

Weyand was posed the question: Imagine a 40-yard dash that races a wide receiver, a safety, an ostrich, an elephant and a pig — who would win?

See the excerpt below for Weyand’s answer.

Read the full story and see the video.

Weyand is an SMU associate professor of applied physiology and biomechanics in the Annette Caldwell Simmons School of Education & Human Development. He lead a team of experts in biomechanics and physiology that conducted experiments on Oscar Pistorius, a South African bilateral amputee track athlete. Pistorius has made headlines trying to qualify for races against runners with intact limbs, including the Olympics.

Excerpt:

Scientific American
If you want to be a professional football player, you’d better start practicing your 40-yard dash. It’s the gold standard for assessing a player’s speed and ability to accelerate, as NBC Learn’s segment on kinematics, motion, speed and acceleration shows.

Human beings need about 10 yards to reach maximum velocity, so the 40 is really a test of both acceleration and speed — unlike a longer sprint, such as the 100, which is more about a runner’s ability to maintain maximum speed. Acceleration depends on how much force runners can put into the ground (and thus receive back) relative to their mass. For this reason, the smaller you are the easier it is to accelerate rapidly. That’s why gymnasts, for example, are generally small — they must be able to generate a large amount of force relative to mass to accelerate enough to run and perform multiple flips in a row. Imagine an offensive lineman trying to do that! Wide receivers, running backs and defensive backs are not as massive as linemen, and therefore are very good accelerators, which is one reason they can handily outrun the latter in a 40-yard dash.

At present, no standard method or variable exists to quantify a human or animal’s top acceleration. One reason: the variable changes with every step until top speed is reached, making a tangible value a moving target. As a result, comparing the top accelerations of humans and other animals is difficult. Nevertheless, it’s true that smaller animals are better at accelerating — think of how quickly a squirrel can dart up a tree trunk, for example.

Speaking of squirrels, imagine a 40-yard dash that races a wide receiver, a safety, an ostrich, an elephant and a pig — who would win? “The ostrich wins pretty easily,” says Peter Weyand, a professor of applied physiology and biomechanics at Southern Methodist University. “And then would probably come the wide receiver, the safety, squirrel, the pig and, finally, the elephant.”

The ostrich, although bigger than a human, is built for speed. “The easiest way to explain why the ostrich is fast is that it has long legs,” Weyand says. It also runs on its toes, and what looks like a backward knee is actually its ankle. Most of the bird’s leg muscles reside on short thighbones, so the task of accelerating and maintaining speed is left to long, light limbs.

Read the full story and see the video.

Weyand is an expert in the locomotion of humans and other terrestrial animals with broad research interests that focus on the relationships between muscle function, metabolic energy expenditure, whole body mechanics and performance.

An expert in the scientific basis of gait and movement, his global interests in muscles and movement have made energy and performance central themes throughout his research career. Weyand’s research and expertise on the limits of human and animal performance have led to featured appearances on CNN, NHK Television in Japan, the Canadian Broadcasting Corporation, the History Channel, City TV of Toronto, CBS Boston and others.

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Popular Mechanics: The Animal Kingdom’s Top Marathoners

An article looking at the abilities of humans and animals to run long distances tapped into the research of SMU physiologist and biomechanist Peter Weyand.

Journalist Brian Resnick in Popular Mechanics cites Weyand’s knowledge to explain the differences at work between humans and animals in “The Animal Kingdom’s Top Marathoners.”

Weyand is an SMU associate professor of applied physiology and biomechanics in the Annette Caldwell Simmons School of Education & Human Development. His experience includes leading a team of experts in biomechanics and physiology that conducted experiments on Oscar Pistorius, a South African bilateral amputee track athlete. Pistorius has made world headlines trying to qualify for races against runners with intact limbs, including the Olympics.

Weyand is an expert in the locomotion of humans and other terrestrial animals with broad research interests that focus on the relationships between muscle function, metabolic energy expenditure, whole body mechanics and performance.

An expert in the scientific basis of gait and movement, his global interests in muscles and movement have made energy and performance central themes throughout his research career. Weyand’s research and expertise on the limits of human and animal performance have led to featured appearances on CNN, NHK Television in Japan, the Canadian Broadcasting Corporation, the History Channel, City TV of Toronto, CBS Boston and others.

Read the full story.

Excerpt:

By Brian Resnick
Popular Mechanics
Compared to other land mammals, humans are remarkably good at running long distances. Our upright posture and ability to shed heat — through sweating — are what allow people to run more than 20 miles during a race. Very few other animals can sustain such distances, especially at the speeds that top human athletes perform. But there is plenty of competition out there — nature is full of species adapted for running distance. Here’s a look at six of the best marathoners in the animal kingdom, from slowest to fastest.

Through years of selective breeding, racehorses have gained a built-in biological mechanism for efficient blood — the kind that certain human athletes can only achieve by doping.

“When they start to exercise, their spleen will kick out a whole bunch of red bloods cells into their system, into their cardiovascular system to make the oxygen carrying capacity of their blood go up,” says Peter Weyand, professor of physiology and biomechanics at Southern Methodist University. Human blood dopers transfuse blood before a race to achieve an increased aerobic capacity. However, the horse naturally release blood cells moments after starting to a gallop.

For the last 30 years, the Welsh town of Llanwrtyd Wells has hoted a 22-mile, man-versus-horse race. Humans have only won the race twice, but top runners usually only finish 10 minutes after the animals. Where horses exceed in oxygen efficiency, humans make up for in temperature regulation. In the beginning of the race the horses tend to have a 30 minute lead, but toward the end, that advantaged is cut to a couple of minutes. Over the course of the race, humans are more efficient at expelling heat — not to mention they aren’t running with a rider on their back. On a hot day, humans can win much more easily.

Are humans born to run? Some experts think that humans have, indeed, evolved to be distance runners — the better to track prey, evade predators and migrate. While there is some debate on running and human evolution, there is no question that we are up there in the animal kingdom for speeds at marathon distances. There is no one reason, but the efficiency of our cooling systems — our ability to sweat — and having an upright posture, to minimize our sun exposure and maximize our lung capacity, are some of the primary reasons we are skilled distance runners.

One major difference between humans and animals is that we don’t have in-born endurance; we have to train.

Peter Weyand says that compared to other animals, humans have a high energy cost of running — we spend more energy in each stride relative to our size. But unlike wild animals, we can motivate ourselves to run, and through training we can increase our aerobic scope — the amount of aerobic activity one can achieve. “Even though

[humans] are good at regulating heat, they have more heat to dump because their economy is poor,” he says. Strict training regimens and the ability to sweat can make up for that lack.
Read the full story.

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Human running speed of 35-40 mph may be biologically possible

2009_Evans_Amber%2Csmall.jpg

Jamaican sprinter Usain Bolt‘s record-setting performances have unleashed a wave of interest in the ultimate limits to human running speed. A new study published Jan. 21 in the Journal of Applied Physiology offers intriguing insights into the biology and perhaps even the future of human running speed.

The newly published evidence identifies the critical variable imposing the biological limit to running speed, and offers an enticing view of how the biological limits might be pushed back beyond the nearly 28 miles per hour speeds achieved by Bolt to speeds of perhaps 35 or even 40 miles per hour.

The new paper, “The biological limits to running speed are imposed from the ground up,” was authored by Peter Weyand of Southern Methodist University; Rosalind Sandell and Danille Prime, both formerly of Rice University; and Matthew Bundle of the University of Wyoming.

“The prevailing view that speed is limited by the force with which the limbs can strike the running surface is an eminently reasonable one,” said Weyand, associate professor of applied physiology and biomechanics at SMU in Dallas.

“If one considers that elite sprinters can apply peak forces of 800 to 1,000 pounds with a single limb during each sprinting step, it’s easy to believe that runners are probably operating at or near the force limits of their muscles and limbs,” he said. “However, our new data clearly show that this is not the case. Despite how large the running forces can be, we found that the limbs are capable of applying much greater ground forces than those present during top-speed forward running.”

2009_Cuington_Ebonym%2C%20small.jpg
SMU sprinter Ebony Cuington. Photo: SMU Athletics

In contrast to a force limit, what the researchers found was that the critical biological limit is imposed by time — specifically, the very brief periods of time available to apply force to the ground while sprinting.

In elite sprinters, foot-ground contact times are less than one-tenth of one second, and peak ground forces occur within less than one-twentieth of one second of the first instant of foot-ground contact.

The researchers took advantage of several experimental tools to arrive at the new conclusions. They used a high-speed treadmill capable of attaining speeds greater than 40 miles per hour and of acquiring precise measurements of the forces applied to the surface with each footfall. They also had subjects’ perform at high speeds in different gaits. In addition to completing traditional top-speed forward running tests, subjects hopped on one leg and ran backward to their fastest possible speeds on the treadmill.

The unconventional tests were strategically selected to test the prevailing beliefs about mechanical factors that limit human running speeds — specifically, the idea that the speed limit is imposed by how forcefully a runner’s limbs can strike the ground.

However, the researchers found that the ground forces applied while hopping on one leg at top speed exceeded those applied during top-speed forward running by 30 percent or more, and that the forces generated by the active muscles within the limb were roughly 1.5 to 2 times greater in the one-legged hopping gait.

The time limit conclusion was supported by the agreement of the minimum foot-ground contact times observed during top-speed backward and forward running. Although top backward vs. forward speeds were substantially slower, as expected, the minimum periods of foot-ground contact at top backward and forward speeds were essentially identical.

According to Matthew Bundle, an assistant professor of biomechanics at the University of Wyoming, “The very close agreement in the briefest periods of foot-ground contact at top speed in these two very different gaits points to a biological limit on how quickly the active muscle fibers can generate the forces necessary to get the runner back up off the ground during each step.”

The researchers said the new work shows that running speed limits are set by the contractile speed limits of the muscle fibers themselves, with fiber contractile speeds setting the limit on how quickly the runner’s limb can apply force to the running surface.

The established relationship between ground forces and speed allowed the researchers to calculate how much additional speed the hopping forces would provide if they were utilized during running.

“Our simple projections indicate that muscle contractile speeds that would allow for maximal or near-maximal forces would permit running speeds of 35 to 40 miles per hour and conceivably faster,” Bundle said.

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Researchers: Pistorius’ artificial limbs give him clear, major advantage

The artificial lower limbs of double-amputee Olympic hopeful Oscar Pistorius give him a clear and major advantage over his competition, taking 10 seconds or more off what his 400-meter race time would be if his prosthesis behaved like intact limbs.

That’s the conclusion — released to the public for the first time — of human performance experts Peter Weyand of Southern Methodist University and Matthew Bundle of the University of Wyoming.

The Weyand-Bundle conclusion is part of a written Point-Counterpoint style debate published Nov. 19 online in the “Journal of Applied Physiology.” Weyand and Bundle were the first two authors of the study publishing the test results acquired as part of the legal appeal process undertaken after the governing body of Track and Field — the International Association of Athletics Federations (IAAF) — banned Pistorius from able-bodied track competitions, including the Olympics.

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SMU’s Peter Weyand and Oscar Pistorius during testing. Marquee photo and inside photos: By Jeff Fitlow/Rice University

In banning Pistorius, the IAAF had concluded on the basis of other data that Pistorius’ J-shaped, artificial lower limbs, called “Cheetahs” by the manufacturer, gave him a competitive advantage over able-bodied competitors. But the ban subsequently was overturned on appeal to the Court of Arbitration for Sport (CAS) in Lausanne, Switzerland.

The case has been considered groundbreaking for the eligibility of disabled athletes and the regulation of prosthetic technology in sport. Pistorius hopes to qualify for the 2012 Olympics.

The newly released conclusion from Weyand and Bundle analyzes the scientific evidence and quantifies the competitive advantage provided by Pistorius’ “Cheetah” limbs.

Weyand says: “Pistorius’ sprinting mechanics are anomalous, advantageous and directly attributable to how much lighter and springier his artificial limbs are. The blades enhance sprint running speeds by 15-30 percent.”

Below the knee, Pistorius’ limbs weigh less than half as much as the limbs of an able-bodied male sprinter.

Bundle notes that most of the 15-30 percent speed advantage enjoyed by Pistorius is explained by how quickly the lightweight blades allow him to reposition his limbs: “Even in comparison to those male sprinters with the most extreme adaptations for speed in recorded human history, Oscar Pistorius has limb repositioning times that are literally off the charts. Usain Bolt is considered somewhat freakish because he outruns his opponents by 2-4 percent. At top speed, Oscar Pistorius repositions his limbs 15 percent more rapidly than six of the most recent world record holders in the 100 meter dash, including Usain Bolt.”

In the aftermath of the IAAF eligibility controversy, both Weyand and Bundle agreed that the initial ban was not scientifically supported and that the May 2008 ruling of the CAS to overturn the ban was sound on the basis of the incomplete evidence considered.
Pistorius’ case was successfully presented by the law firm Dewey & LeBoeuf of New York.
“We are pleased to finally be able to go public with conclusions that the publishing process has required us to keep confidential until now. We recognized that the blades provide a major advantage as soon as we analyzed the critical data more than a year and a half ago,” said Weyand and Bundle in a statement.
Speaking for both investigators, Weyand said: “We admire the unique athletic achievements of Oscar Pistorius and are grateful for his willingness to share these important results for the general benefit of athletes and athletics.”
A different interpretation of the Pistorius data appeared as part of the written Point-Counterpoint style debate in the “Journal of Applied Physiology.”
Weyand and Bundle based their conclusions on data indicating:
Pistorius’ lightweight blades allow him to reposition his limbs 15.7 percent more rapidly than five of the most recent former world-record holders in the 100-meter dash.
The springy, lightweight blades allow Pistorius to attain the same sprinting speeds while applying 20 percent less ground force than intact-limb runners.
The springy blades reduce the muscle forces Pistorius requires for sprinting to less than half of intact-limb levels.
Peter Weyand is an associate professor of applied physiology and biomechanics in SMU’s Annette Caldwell Simmons School of Education & Human Development.
Matthew Bundle is an assistant professor of biomechanics in the College of Health Sciences at the University of Wyoming.
Read news coverage of this story.
Related links:
JAP: Point-Counterpoint “Artificial limbs do/do not make artificial running speeds possible” target=blank
JAP Study: The fastest runner on artificial legs: Different limbs, similar function?
Science Daily: Oscar Pistorius, amputee sprinter runs differently
New York Times: An amputee advantage?
Times: Oscar Pistorius to make run at London 2012
Study revives Olympic prospects for amputee sprinter
T.O. Sports: Blade runner beats the ban and his ‘Cheetahs’ are no longer ‘cheating’
AFP: ‘Bladerunner’ Pistorius wins appeal against Olympic ban
IAAF: Pistorius is eligible for IAAF competition
New York Times: Amputee ineligible for Olympic events
TIME Magazine: How Fast Can Humans Go?