Carbon-fiber prosthetics good as gold for Leeper

Comments Email Print
sampics Photographie/Christina Pahnket photo Blake Leeper crosses the finish line as he and his U.S. teammates set a world record in the 400-meter relay at the Paralympics world championships in Lyon, France. Leeper, who was born without lower legs, is wearing carbon-fiber running blades.

CHICAGO — It's easy to find the video from the final moments of the finals of the men's 200-meter sprint during the 2012 Paralympic Games in London.
Most of the attention from the announcers at the T42/T43 race — for athletes with at least one prosthetic leg — goes to the two men who crossed the finish line in first and second place, as Brazil's Alan Oliveira beats out the favored Oscar Pistorius of South Africa.
But keep your eyes on the two men just behind them. Blake Leeper of the U.S. and Arnu Fourie of South Africa are side-by-side, closing in fast.
For Leeper, just being there is part of a rapid change in his life, carried forward by advances in materials, technology and engineering.

In this Plastics News video, see award-winning Paralympian Blake Leeper in action.

Born without lower legs and spending his entire life using prosthetics, it's only been three years since he got his first pair of carbon-fiber running blades and unlocked the athlete he always knew was inside of him, waiting to explode.
And now, on the day before his 23rd birthday, he's in a race of microseconds with just inches to go, willing himself to somehow cross the line just ahead of the man next to him.
"I knew it was going to take something crazy to get on that podium," Leeper said.
So at the last moment, he dives head first across the finish line, scraping his skin on the track. When he lands, he accidentally trips Fourie. They help each other up and then wait.
And wait.
It takes almost a minute — more than twice as long than the race itself — until the scoreboard finally lists the winner of the bronze medal. Blake Leeper, by three-hundredths of a second, in 22.46 seconds.
A few days later, he wins the silver medal in the 400-meter race.
In August, he and his U.S. teammates win the gold medal in the 400-meter relay at the world championships in Lyon, France, setting a world record in the process.
But during an interview at the Industrial Designers Society of America annual conference in Chicago just a week after that world record, Leeper comes back to those three-hundredths of a second in London.
He has a question for materials experts, engineers and designers: Is it possible they can help create even more improvements to those blades? If diving across the line was the difference between a medal and no medal, imagine what could happen with improved aerodynamics or lighter and thinner composites or a refined curve.
"We can take this to a whole new level," he said.

Keeping the faith

Speaking to groups like the IDSA, Leeper likes to quote college football's Lou Holtz, who once said life is "10 percent what happens to you and 90 percent how you respond to it."
On the day Leeper was born, his parents first knew something was wrong when he was rushed out of the delivery room.
When the doctors came back to them, they were told that their son would never walk, would possibly use a wheelchair for his entire life and would never play sports. He said his parents kept a positive attitude despite the warnings.
Leeper got his first pair of prosthetic legs when he was 9 months old. He jokes that the plastics industry was part of him from the day he was born. He grew up in Kingsport, Tenn., where his father, Billy Leeper, and many other relatives worked for Eastman Chemical Co., and his father's insurance plan from Eastman covered the costs of his walking legs.
Eastman has supported Leeper's outreach — including a "Leep into Fitness" meeting with children in Kingsport after the 2012 Paralympics — although it does not directly supply any materials used in his prosthetics.
As part of an athletic family, Blake Leeper did his best to keep up with his friends, playing baseball and basketball. He was so active, he continually broke the lightweight prosthetics designed for most children.
When he was 8 years old, he was fitted for a sturdier pair of "walking legs." Those legs used some carbon fiber in a shock system that would give him more function and durability.
He used them through high school, playing as a catcher, infielder and outfielder in baseball and even making the varsity high school basketball team, learning how to adapt.
"In a way it was helping me. I was developing muscles that if I did have blades at a young age, maybe I wouldn't have developed the same way," Leeper said. "They made my back a little stronger and my hips a little stronger because the legs are a tad bit heavier than I was used to.
"But at the same time, I didn't know any better about that. I'm just trying to keep up with my friends. I'm trying to make a spot on the basketball team. I just want to not finish last. I'm just trying not to get cut."
It wasn't until the Paralympic Games of 2008 in Beijing that he first became aware of carbon-fiber running blades.
The first versions of a carbon-fiber running foot came out in the late 1970s. Inventor Van Phillips launched his company, Flex-Foot, in 1984. The Flex-Foot Cheetah was designed to work like a spring, absorbing energy as it hit the ground, and allowing a runner to use that energy in the next stride. Phillips sold the company to Reykjavík, Iceland-based prosthetics maker Össur in 2000.

Four years later, South African prosthetist Francois Vanderwatt outfitted one-time rugby player Pistorius with his first set of blades. Pistorius' success on the track brought the blades new international attention, including coverage of Paralympics races that Leeper first saw when he was a physics student in college.
He immediately began doing research, but quickly found out that running blades do not come cheap. They can cost as much as $30,000. Each pair is custom made, designed to fit on each athletes' body specifically.
"Given that my parents were helping me with my education, I highly doubted that they were going to buy me a pair of running legs. I said that you're going to have to figure this out on your own."
Leeper looked at the roster of Paralympians from the U.S., then narrowed them down to athletes in the South. He made contact with one who had grown up in Nash¬ville, just two hours from Kingsport.
He told him his story, then followed a line of contacts leading him to the Challenged Athletes Foundation in San Diego, which invited him to a clinic for disabled athletes. He worked out using his standard walking legs, but quickly drew attention.
"At that event, it was very evident that Blake was a guy who was going to be a star," said Roy Perkins, senior director of programs and marketing for CAF.
The U.S. Paralympics program does not provide funding for running feet, so CAF works with Össur on a grant program that helps finance up to 40 feet and knees each year.
"Running feet are not considered medically necessary," Per¬kins said.
In addition to the cost of the material and engineering that goes into the blade itself, each prosthetic is custom-fitted to the athlete. The thermoformed socket, which attaches to the athlete, is so sensitive that if the runner loses a few pounds, it may need to be re-molded.
Leeper won one of the grants from CAF, with his blades made by Vanderwatt, the same man who made Pistorius' first blades.
"You have to imagine that my whole life, I was only able to run so far," Leeper said. "I pushed those limits playing sports. I tried as hard as I could to keep up and just like that, I'd seen them on TV and it changed. And then they gave them to me and said: 'Here. They're yours.' "
At the track, the first time Leeper tried on his blades, he was warned it could take months to get used to the way they moved and the way he'd feel.
"I was kind of scared. I was thinking, 'Go slow, go slow,' " he said. "I was on a curve and I was just going slow and going slow. Then I hit the straightaway and I just opened it up and the way the wind hit my face, I've never felt that before in my life. I was something I couldn't explain because I'd never felt that before."
A few months later, in June 2009, Leeper headed to his first track meet. He was hoping he wouldn't let down his family, who had come to watch him. He won three events and qualified for the U.S. Paralympic team.
In August, he won both a silver medal and a bronze medal at his first international track meet, in Rio de Janeiro.
"Just by a pair of legs being presented to me, I was doing things I never had before. I always knew that I was an athlete. I always knew I was competitive in sports, but to take it to a Paralympic level, that's something that I never thought I could compete on at any level."
Even as a full-time athlete now, training up to six hours a day in California alongside able-bodied Olympians, Leeper has continued to help others tap into their potential.
He was part of a CAF group that traveled to Haiti after the 2010 earthquake devastated the capital city of Port-au-Prince, leaving thousands dead and injured.
There, the group encountered not only physical complications but emotional ones. A group of children at one camp laughed off the idea that an amputee could be an athlete, Perkins said. The fastest able-bodied boy challenged Leeper to a race. Leeper not only won, he changed the minds of everyone who saw him.
"They followed him everywhere," Perkins said. "They thought he was a superhero."
Leeper has plans to compete on an even higher level, and he thinks engineers and designers can help him and other athletes achieve more. Beyond his own hours of training, trying to get the most out of his body, he's hoping to encourage others to look at ways they can bring their skills to improve the blades, both in performance and in making them available to more people.
The carbon-fiber blades have been in wide use for about 10 years, Leeper said.
Current blades use 30-60 sheets of carbon fiber, depending on who is using them and how they are being used. The shape, curve and precise measurements of the blade depend on the running style of the user and the type of race they are used in. A 100-meter sprint blade, for example, has the curve at a higher point than those used in a 400-meter run.
The blades weigh less than 2 pounds each. The heaviest parts of each are the metal bolts that connect the blades to the socket.
"The blade is the interesting part," he said. "Can you thin the blade down? Can you move the curve? What about the aerodynamics of the blade, can you put something on it that would make it cut through the air better? Can the toe be longer or should it be shorter?"
Too much spring to the blade, and a runner can lose his or her balance; too little and they're not competitive.
Some runners like a thicker blade that will give them more power on each stride. Leeper's style favors a fast turnover and a quick stride, so he prefers blades that are lighter. Each slight change he makes gives him immediate feedback.
"You have to figure out between which category gives you enough energy return, but not too much," he said. "Personally, I haven't even felt like I've found 'my pair' yet, the pair that hits my sweet spot on the blade. It may take two or three years yet to figure that out."
Leeper has set himself a goal not only of competing at the 2016 Paralympic Games, but qualifying to run alongside able-bodied competitors as a member of the U.S. Olympic team. It will take a lot of work, he said, and improvements to the blades along with his own work and improvements are creating a pathway to that dream, though.
"Think back to that three-hundredths of a second, and if we can get into the labs and think about shaving just tenths of a second off, we're breaking world records," he said. "One day I believe the fastest man in the world will be wearing blades, and I'm hoping that person will be me."