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Do blades give runners an unfair advantage?

Editor's note: Second of a two-part series exploring the issue of whether carbon-fiber prosthetic blades give Hunter Woodhall and other amputees an unfair advantage over flesh-and-blood legs.

Separate Paralympic competitions were created years ago for amputees to compete against one another, but the development of prosthetics became so advanced that it enabled the best of them to compete against able-bodied athletes at the highest levels.

But is it fair — for able-bodied athletes?

Consider this: Since 2000, Utah's all-class state record for the 400-meter dash had improved by .01 of a second — that’s one-hundredth of a second — to 47.00. In a single season, Syracuse High's Hunter Woodhall took it down to 46.24 — a staggering improvement of .76.

The issue of fairness has been hotly debated at the international level, most notably when South Africa's Oscar Pistorius rose to prominence. He not only qualified for the able-bodied 2012 Olympics, he advanced to the semifinals. But to get there he had to win a court battle.

In 2008, the International Association of Athletics Federations ordered a series of tests conducted by 10 scientists to determine what, if any, advantages his high-tech blades might give him. The study concluded that Pistorius used 25 percent less energy to run at the same speed as natural athletes; the amount of energy return of the blade — the power generated by a foot strike — has never been measured for a natural ankle joint (reportedly three times higher); and the energy loss in the prosthetic blade was 9.3 percent, compared to 41.4 percent for a natural ankle joint.

Dr. Peter Bruggeman, a professor of biomechanics, told the German newspaper Die Welt that Pistorius "has considerable advantages over athletes without prosthetic limbs who were tested by us. It was more than just a few percentage points. I did not expect it to be so clear.”

The IAAF banned Pistorius from its competitions, which include the Olympics. Pistorius appealed to the Court of Arbitration for Sports and won, largely based on the findings of another study at Rice University, which reported flaws in the IAAF study. It was decided that the IAAF tests had not considered problems that were unique to blade runners — specifically, running the turn and using starting blocks. But even the scientists in the Rice study couldn’t agree on the results. As reported by Scientific American, members of the Rice team later began to disagree widely on their conclusions, one grouping claiming Pistorius had no advantages and the other claiming he had serious advantages.

Scientists Peter Weyand and Matt Bundle said Pistorius’ faster leg swings and energy-efficient stride could create a whopping seven-second advantage in the 400.

“The more mass you have closer to the axis — in this case, your hips — the easier it is to stop the rotation and then turn it around,” Bundle told Scientific American. “Whereas if you had that same amount of mass located a long way away from the axis — in your legs and feet — it becomes much more difficult to stop it and get it going in the opposite direction.”

To put this assertion to the test, try doing leg raises — the straighter the leg, the farther the feet (and their weight) are from the body core, the more difficult it is to lift them.

Other scientists — Hugh Herr, Alena Grabowski and Roger Kram — determined there was insufficient evidence for such claims. Grabowski contended, based on her studies, that athletes with prosthetics are at a disadvantage against able-bodied athletes because they can’t apply as much force into the ground.

Cathy Sellers, director of U.S. Paralympics, does not believe Woodhall has any competitive advantages with the blades. She believes that because Woodhall’s condition was congenital and therefore “he was not born with everything,” that he never had an opportunity to develop, in his case, quadriceps and hamstrings, as he might have if he had his lower legs amputated later in life.

“They don’t have the strength others do in certain areas,” says Sellers. “They have to work on core and hip flexors.”

This is especially true for Woodhall, whose femurs did not grow as expected and are, in his words, “shorter than they should be.”

Two years ago, Grabowski made a presentation to the NCAA, again claiming there were no advantages and that there might even be disadvantages. The NCAA has rules that seem to at least question the use of blades. Appendix F of the rulebook states a reasonable modification or accommodation will be allowed if it does not “provide the student-athlete an unfair advantage over other competitors.”

The rulebook also states: “Incorporating any technology and/or device in the shoe’s construction that artificially enhances a competitor’s performance is not permitted.”

But based on Grabowski’s assurances, the NCAA effectively opened the door for running prosthetics when it cleared the way for Harvard sprinter Nicky Maxwell to compete. Maxwell had his right leg amputated as an infant and uses a prosthetic to run.

Maxwell’s times are very modest by able-bodied standards, though. The NCAA has never seen anyone like Woodhall. On blades, he is a force with which to be reckoned, and that could cause some heartburn in the collegiate ranks, just as it did at the prep level. “I don’t know how USATF (United States Track and Field) will embrace him with those blades,” says Joaquin Cruz, who has coached Woodhall for the past two years. “But I can see him competing with able-bodied athletes in the U.S. championships and Olympics.”

Dr. Craig Poole, the former head track coach at BYU, worked with disabled athletes for years as director of the Olympic training center. Ask him what, if anything, should be done about blade runners competing in able-bodied competitions, he says, “I have not thought about it because we haven’t had anyone come up who is as good as (Woodhall). Once he gets up there, or someone with special talents, they’ll see there are advantages. There’s absolutely no question this issue will come up.”

Poole, who served on the NCAA rules committee when rules regarding the use of prosthetics were written, continues: “Anytime you use technology to enhance someone’s performance, there’s an advantage. There is no question there’s a disadvantage at the start of the race. Initiating the movements to begin with is a problem. But once they get running they take advantage of the technology to enhance their performance. Go back to the rules; athletes cannot use any spring-type device to help performance. Technology has helped them to super compensate to overcome a disadvantage.”

Poole believes limits need to be placed on the amount of spring that the blades can generate (the aforementioned “energy return”) — “Most (blade runners) have a turnover rate that is no higher than regular athletes, but the length of the stride is tremendous,” he explains. He also believes the length of the prosthetic should be limited. Many Paralympic athletes add 2 to 4 inches to their height (Woodhall says his blades make him about an inch taller). The extra height allows the athlete to increase stride length, as Usain Bolt has demonstrated so dramatically. Stride length + stride rate = speed.

“(Woodhall) is a phenomenal talent,” says Poole. “I hate to put pressure on the kid, but he’s better than Pistorius. He’s going to be the best in the world.” Pistorius’ best time was 45.07. Woodhall, at 18, already has run 46.23, not to mention a 45.6 relay split at the state championships. Roger Buhrley, who coached Woodhall earlier in his career, was at a track clinic a couple of years ago at the Olympic Oval in Salt Lake City when he was approached by an expert in biomechanics who had studied Woodhall.

“He pulled me aside and told me Hunter’s got the potential to be better than Pistorius,” says Buhrley.

Cruz believes a generation of top double-amputee sprinters is on the rise, the legacy of Pistorius before he was found guilty of murdering his girlfriend, and that means the issue of fairness likely will be raised again. Germany’s David Behre and New Zealand’s Liam Malone have run 400s in the low 46s (Malone is just .11 off his country’s able-bodied national record) and Cruz believes Nick Rogers will join them soon. At the U.S. Paralympic Championships in Los Angeles, held in early June, Woodhall finished second to Rogers in the 200 and second to Austin Digby in the 400.

To compete at the international level, they would have to run the 400 in the range of 44-45 seconds. Given the conflicting results of testing, and as more and more blade runners challenge able-bodied runners, Cruz believes “more scientists are going to develop an interest in these kids and they’re going to have to do better studies.”

Pressure is building for conclusive results. Markus Rehm, a Paralympic long jumper from Germany who wears a prosthetic on his right (jumping) leg, attempted to enter last summer's Olympic Games but was denied by the IAAF. His best jump of 8.40 meters would have won the last three Olympics. Acknowledging that it is a “really complex,” situation, he wants to compete in this summer's able-bodied World Championships but not be allowed to win a medal.

For his part, Woodhall says, “Obviously, I have advantages, but I also have disadvantages.” He believes the advantages are offset by the disadvantages he faces with the start of the race. As a high school track coach for almost 30 years, I believe that is true only to an extent. I believe it all evens out at about 150 meters, and after that a runner on blades has a tremendous advantage over able-bodied sprinters.

A comparative analysis of elite performers shows that you can determine a sprinter's best 200-meter time simply by doubling his 100-meter time. The formula is remarkably accurate for the state's top able-bodied prep sprinters this spring. The variance between the second half of the 200-meter race and the first half for Landon Maxfield and William Prettyman was -.04 and +.04, respectively. Dallin Draper ran the second half of the race .31 slower (his best 100 had a tailwind of 2.0 meters per second, the highest allowed without being considered wind-aided, thus skewing the comparison). Dominic Bentil had the best variance, running the second half of the race .12 faster than the first half.

By comparison, Woodhall's variance was a whopping .95 faster — almost a full second. If he ran the first half of the 200 in 11.06 — his best time during the prep season — he had to run the second half in 10.11 to finish in 21.17 — his winning time at state. Even if he ran a faster opening 100 that particular day, it wouldn't be enough to account for such a huge variance. In the 2009 world championships, Usain Bolt set the world record for the 100 in 9.58. Do the math: 9.58 x 2 = 19.16 for 200 meters. His world record for the 200, set in the same meet, was 19.19 — a variance of +.03.

Separate Paralympic competitions were created to give Paralympic athletes an even playing field, but with the advent of technology, maybe it’s the able-bodied who need an even playing field. Some serious consideration should be given to placing blade performers and their records in separate categories, as Track & Field News has done.

In the era of political correctness and "inclusiveness, it is reasonable to wonder if scientists and sports officials can reach an objective conclusion. As Poole says, referring to future testing efforts, “I hope their decision is based on real science, not emotion — not social pressure or political correctness.”

The obvious question is would Woodhall be this fast if he had his natural legs? Buhrley says no, but for reasons that are different than you might think.

“I get asked a lot whether (the blades) are an advantage,” he says. “I’ve concluded it is for him. I really believe if he had never had any obstacles — if he had had normal legs — I don’t think he would’ve worked as hard; he wouldn’t have had anything to prove. And he wouldn’t have had the same opportunities — going to the training center, and all the coaching and diets and testing. There’s no way of ever knowing if he would have been this fast, though.”