The future of modern prostheses' usage in sports hangs in the balance, and the fight is getting ugly.
In a point-counterpoint published by the Journal for Applied Physiology today, Dr. Peter Weyand of Southern Methodist University and Dr. Matthew Bundle of the University of Wyoming claim sprinters' prosthetic legs can shave more that 10 seconds from a runner's 400-meter.
Dr. Rodger Kram of the University of Colorado and his colleagues' response: "You cannot be serious!"
In May 2008, the experts on both sides of the argument worked together to overturn the IAAF's ban on prosthetic legs in professional sprinting. The ban remains overturned, but now, with the data from an 18-month study made public, very different conclusions have arisen over what the data actually means. The question boils down to this: Is it the prostheses or raw athletic ability that allows South African double-amputee sprinter Oscar Pistorius to run so fast?
"Personally, I find it preposterous, ludicrous, to suggest that amputating my legs and giving me prostheses would make me run 12 seconds faster over 400 meters," says Kram. "Take away all the muscles in my calf and foot, and I'm going to run faster?"
The ban was rescinded, but the new data seems little more conclusive as research team members draw lines in the sand. On one side Weyand and Bundle found what they believe is solid evidence that Pistorius's prostheses give him a clear advantage over other sprinters. But Kram, along with other colleagues that include Dr. Hugh Herr of MIT's Media Lab, claim "indisputable" evidence to the contrary.
"It's important to note that this is not a new study by Weyand and Bundle," Kram says. "It's an opinion piece that has not been peer reviewed."
The study Kram refers to is Weyand and Bundle's comparison of Pistorius to physiological data collected on other sprinters. "Oscar swings his legs faster than anyone we've ever seen in the history of sports or science," Bundle says. "In fact, it's significantly faster. If you compare Oscar to six of the former and current world record holders, he swings his legs 15 percent faster."
Kram and his colleagues at MIT have since been collecting data on a different set of sprinters – single-limb amputees – comparing the way they swing their natural legs to their artificial ones. "We decided that a study of unilateral amputees would provide good insight because you can compare the prosthetic leg to the biological one," he says. "It gave us good control."
They determined that prosthetic limbs produce lower ground reaction forces than those of the average sprinter, a fact Weyend and Bundle don't dispute. But Kram and company also argue that while Pistorius' leg repositioning time is swift, it's not unnaturally so. Rather, his repositioning speed is driven by his athleticism; Pistorius, through training, has compensated for reduced ground force with blazing leg speed.
Weyand and Bundle fire back that Pistorius's speed is in no way natural: "Even in comparison to individuals with the most extreme gait adaptations for speed in recorded human history, the double-artificial-limb value is not simply an outlier; it is quite literally off the biological charts," they write. This ease of acceleration could trim 12 seconds off a 400-meter runner's time.
Back and forth it goes. Kram and company cite Weyand's previous writings claiming vertical ground reaction force is the key determinant of sprinting speed. Weyand and Bundle respond that "more erect limb posture" in leg-amputees, coupled with lower ground force "co-reduce the muscular forces required to attain the same sprint running speeds to less than half of intact-limb levels," saying Pistorius needs half the strength to reach the same speeds as runners on biological legs. Kram and company respond with the affronted incredulity of a John McEnroe.
Neither side of the argument wants to see amputee sprinters banned from competition, but they have different visions for the future of the sport. Kram's side sees no problem letting amputees sporting Cheetahs take to the starting blocks. Weyand and Bundle suggest redesigning the prostheses to remove perceived advantages. "As for Oscar, there are some pretty simple things that could be done to his prostheses that could remedy the advantages that we've found," Bundle says.
Could an age of running where prostheses are approved for competition by sanctioning authorities solve the problem? It's possible, but not likely. Each runner is different and thus a standardized prosthetic would be difficult to implement. Further, how does a governing body put limits on how fast an athlete can reposition his legs and still call it an open competition?
The point-counterpoint article published today hopes to wring consensus from the scientific community. The piece will remain on the Web for months, soliciting responses from other scientists, some of which will be digested into another paper representing the feelings of the larger scientific community.
A rare point of agreement: more research is necessary. "When you think about it, the world has only studied one bilateral amputee runner, and he happens to be the fastest," Kram says. "One would think that before leveling an opinion on this, the scientific community should conduct more research."
Regardless of what further research shows, either prostheses will be banned from professional sprinting or they will be permitted in some form. The former outcome will dash the dreams of many, and the latter will invite skepticism that amputee sprinters' achievements are truly their own (Barry Bonds and the asterisk comes to mind). For athletes like Pistorius, that means waiting in athletic purgatory until science decides whether the lack of biological limbs constitutes a handicap or a performance enhancement.
For someone used to moving so fast, the wait must be interminable.
For more on the issue, definitely see double amputee sprinter Aimee Mullins's recent guest-edit stint at Gizmodo, and her piece Racing on Carbon Fiber Legs: How Abled Should We Be?
OK. He should not compete just on the fact that he is different. Men and Women are different so they don't compete together. I am not saying one is better than the other im just saying that it will be to hard to judge if there is a enhancement or not ever. You could say that a mans ability to grow significantly larger muscles than women is an advantage but we don't. We accept the face that they are different.
At first blush, I thought "Oh God, don't scientists have anything better to do. . ."
Then I thought further: Since the winner in these competitions is determined by Seconds or less-- eliminate the Lower Calf and Foot-- along with BONE and watery flesh and replace it with a LIGHTWEIGHT laminate or whatever space-age flex material the prosthesis is and you've changed the Bio-metrics of Mass & inertia. There may very well be LESS weight to pull and less Inertia to overcome as the upper legs scissor the lower extremities. Granted the runner is penalized with the loss of muscular control and foot-sole 'Grip' of the running surface, etc etc. But still. . .
So the question is-- How much weight is there in the missing limb? Perhaps we can get this rather macabre answer without having to wait for another twistedly 'informative' chapter in the SAW franchise.
look the answer is here. DO OUR LEG BONES BEND AND SPRING FORWARD WHEN WE RUN? no of course they don't duh! the prosthetic sport legs are very similar to leaf springs in horse carriages and very old antique cars. carbon reinforced metal, plastic or concrete; notice that when you add carbon to any solid matter it makes it 10x stronger and flexible! remember the article about flexcrete? maybe they should have a different league for sports with these legs. men and woman are seperated when it comes to sports. they should have their own. there. done.
The article points out just how much research is being put into solving the question. More needs to be done until clear eveidence shows us that artifical limbs do give an unfair advantage.
This is idiocy. Common sense alone tells us these things grant an unfair advantage. Time the guy running a race without them, then time him with them on. In one, he has world class speed, in the other, you need a calander.
They are performance enhancers, in that they enhance his performance past his physical capabilities. Are you saying that if science made me the 6 million dollar man it would be fair for me to compete, just so long as I almost always came in second?
This is not an issue of "equal playing field." That would be something like the swiming super-suits, which they had to offer to everyone before they were allowed. Thus, no one can argue that Phelps was the fastest, because everyone had them on.
On the other hand, no one really believes that Phelps beat all those world records fairly in equal competition. The suit gave him an unfair advantage against previous records.
Thus, while these artifical legs are great, and this guy should have a great time at the special olympics, he unfit to run in the Olympics without special assistance, which, of course is not to be allowed.
After all, if my grandma's jazzy chair doesn't give her an advantage over the other sprinters, can she be in the olympics? It is just equaling out the playing field against her disability (being 96). After all, it can't be too unfair, since most sprinters can outrun her chair.
Oakspar and ggouge, you guys nailed it. Regardless of whether or not they make you better then the competition, its simply not fair to lump prosthetic runners, and non-prosthetic runners in the same group.
@Marrach: I was thinking the same thing, those prosthetics have to weigh a LOT less then what they're replacing, was this taken into account for the research?
and finally @gammaraylaser... How much thought did you really put into your comment? Joints (like our ankle) provide the same "bending and springing" action you seem to think we're missing.
What’s really interesting to me about this is that not too long ago people with amputated limbs were looked at very differently, they were considered handicapped.
Now we are trying to debate if they have the right to compete with “normal” people because of the advantages they have.....
It seems to me the real advantage or disadvantage people have exists only in our perception of them....
I think you've distilled the argument pretty well right there. In writing this piece I (obviously) spoke to parties from both side of the argument. One claims the time when artificial limbs surpass the performance of our own has come and gone. The other thought it ridiculous that removing the intricate machineries of muscle, tendon and bone in our lower legs could somehow enhance overall performance. We seem to be stuck in a gray area right now, but it's inevitable that technology will at some point decidedly overtake our biological abilities.
The next generation of prostheses, driven unfortunately by the number of young men and women returning from Iraq and Afghanistan without their biological limbs, are going to challenge those perceptions even more. For more on that, I highly recommend checking out that piece by Aimee Mullins that we link to at the end of the above story./cd
I'm sorry guys but it's not the same. Case in point:
- The guys has the carbon fiber absorbing every shock/step in it's molecular structure and then releasing that energy to his advantage on the launch to the next step. Whereas, a normal runner without prosthetic, has to do double-time, when their calf muscles first of all, work hard to absorb the shock of the forward step, then they also have to propel the runner to the next step. There's no storing of kinetic energy in human tissue. So the normal runner, expends way more energy trying to stay running, whereas the one with no legs sort of bounces along like a trampoline, somewhat.
- The reduced weight of having no lower legs also adds an advantage over he with legs.
It's one thing to feel sympathetic towards a double amputee, but it's an entirely different issue to call them one-and-the-same. That is just NOT true!!!
The guy has no legs below the knee. Clearly this is an unfair advantage. If he wants to race against the two-leggers they should handicap him so that he doesn't have an unfair advant......... oh wait.
There's no way to know for certain because we can't test how he'd run the same day under the same conditions, but with his legs intact. So, on some level, those reams of data they're arguing over are meaningless.
It seems patently obvious that what he is doing is different from what the other runners are doing. So, sorry, but he should be in his own category, not too much different from the wheel chair runners. Do the wheel chairs give them an advantage? Why even ask the question? It's a different event. Period.
The day he runs on a sore ankle or stubs his toe is the day he can claim to be like the other runners.
Well no matter what we are going to have to ask these kinds of questions in the near future.
What about artifical arms in sports, or brains in Who Wants to be a Millionaire? Stomachs in eating contests?
The competitive fields are going to start looking like automotive shows with whoever has the best parts wins.
@ tim maguire
There are plenty of ways to test weather or not amputies have an unfair advantage or not. We can test the restriction of airflow along the limb, differences in force exerted along the running surface, and others.
First question, was this guy a sprinter before he lost his legs? If so what were his best times? compare that to what he's running now. If he shaved off 12 seconds thats a pretty clear advantage.
Second question, If this guy has the cojones to be a sprinter after he lost his legs shouldn't he be allowed to run? I don't see a level playing field for him in the special olympics really. I think he could totally take a guy with arm crutches. I mean look at him he is an athlete.
Third question, Isn't it true technology affects most sports already? Baseball bats, golfballs, golf clubs, football pads, Hockey gear? This guy has legs.