The shoelace is worn and frayed, with loops tied at each end. David Brown curls his fingers tightly around one loop, then Jerome Avery grabs the other.
"Four inches," David says. "That's all we have between us."
The sprinters keep hold of the cord as they burst from the starting blocks, charging side-by-side down the track.
"Pick it up," Jerome growls.
Their arms pump in unison and their legs churn in identical strides so that, on a hushed autumn morning, they sound like one person running. David moans with exertion.
"C'mon," Jerome tells him. "Drive."
No blind athlete has ever run 100 meters as fast as David. A relative newcomer to his sport, he recently broke the 11-second barrier, putting his best time fairly close to the 9.58 world record set by track superstar Usain Bolt.
Each dash toward the finish line is an explosion of effort, the 23-year-old pushing his body to the verge of losing control. It is also a test of faith because he must rely upon Jerome, his sighted guide, to keep him running straight and safe.
There is much work to be done as they train at a national team center here, preparing for the upcoming Paralympic world championships. David tends to lean a bit left when he sprints, dipping his head ever so slightly toward Jerome. He is worried about losing contact with his partner, and this imperfection could rob them of precious time.
"Not good," says their coach, Joaquim Cruz, watching from the infield. "The trusting is the hard part."
The boy was 15 months old when Kawasaki disease attacked his eyes. Within five or so years, it became evident no treatment could stop the malady from slowly devouring his sight.
Life changed for David, an optimistic kid who often punctuated his sentences with unexpected laughter.
"I always loved to play basketball," he says. "But the ball started to find my face."
His mother, Francine, insisted there would be "no sitting around." In 2004, she moved David and his older sister from Kansas City to St. Louis so he could attend the Missouri School for the Blind, where he wrestled and played goalball, a sport for visually impaired athletes in which teams throw a ball that makes noise at each other's goal.
A P.E. teacher noticed him racing classmates across the schoolyard and suggested he sign up for track.
"David was kind of skeptical at first," Francine recalls. "But he eventually came into the light."
His times quickly improved, drawing the attention of national coaches. In 2008, he won an essay contest to attend the Paralympic Games in Beijing.
At that point, the 15-year-old could make out only vague shapes and colors. It was the sound of the crowd that got to him.
"I came back home and wrote out a lifetime plan," he says. "I wanted to run fast."
Built slim and strong,
he continued to rise through the ranks of blind sprinters, performing well at the
"When I got here, everything clicked," he says. "This was where I belonged."
Making the 2004 Athens Games figured to be a long shot for Jerome. His times weren't quite fast enough.
Failing to advance past the 100-meter quarterfinals at the U.S. Olympic trials, he resigned himself to heading back home to Central California.
A friend suggested another option.
The U.S. team needed guides for the blind sprinters and jumpers who had qualified for the Paralympic Games, which would take place soon after the Olympics, in the same city. Jerome recalls: "I'd never been to Athens."
It takes a specific kind of athlete to be a guide, and the talent pool is exceedingly small, consisting of runners who possess elite speed but have fallen short of Olympic standards.
"Very hard to find," says Cruz, a gold-medal runner for Brazil in his youth.
Within months of joining the program, Jerome accompanied the team to Greece where he displayed a skill for mimicking other athletes' arm swing and stride. It was like running a three-legged race — partners who moved in sync could save tenths of a second.
Preternaturally talkative, Jerome also shouted advice while he ran. That booming voice matched his imposing appearance — the clean-shaven head and thick muscles. Cruz says: "You can hear him all the way across the track."
There was another characteristic — maybe the most-important one — that helped Jerome in his new job. Unlike so many talented sprinters who had come and gone through the program, he was willing to put his own dreams on the back burner.
"I thought running for myself was my goal in life. I was good at it," the 36-year-old says. "Come to find out, I'm really good at guide running."
By the spring of 2014, David had a problem. He was excelling on the international circuit and,
quite simply, running too fast for his guide at the time. Cruz went looking for someone who could match the new star's speed and intensity.
"David is an A-type personality … always coming to workouts a half-hour early and I ask him, 'What are you doing here?'" the coach says. "We had to find a guide who was the same."
Though Jerome possessed the requisite speed, his running style was not a perfect fit. He was a technician — "a pretty runner" he calls himself — while David relied on brute strength. Cruz asked them to test the partnership for a few weeks.
David ran a personal best in their first race together and went even faster the next time. Within a few months, he had set the 100-meter world record for totally blind sprinters at 10.92 seconds.
"There was no doubt in our minds after that," he says. "Yeah, this was going to be a lifetime match."
The connection is obvious as they arrive for a morning session at the training complex. Jerome yawns out loud and, immediately, David begins to goad him, urging him to snap into shape.
They jog and skip along the track — no need for a tether during warmups — and their banter soon morphs into jokes. The sweat shines across their faces as Jerome says: "I'm awake now."
The workout turns serious when Cruz has them refine their drive phase, the crucial first steps that generate momentum. Now Jerome takes the lead, barking encouragement.
Each sprint becomes a subtle dance, Jerome always on the left, David on the right. The guide gently tugs the tether or nudges with his forearm, keeping his sprinter in line without doing anything that might disrupt their cadence.
"There you go," Jerome yells as they fly through the first 200 meters. "Stay tight."
Cruz watches from beneath a canopy, shading himself from the rising sun. He offers occasional advice but with runners this skilled, with the championships so close, he prefers to let the men work it out between themselves.
Even with all that David has accomplished, even with all those victories piling up, doubt still lurks.
"You think, 'Don't run me into anything,'" he says. "You have that fear."
Early in his career, a guide accidentally let go of the tether, which sent David careening into another competitor. More recently, in a 200-meter heat at the 2015 Parapan Am Games, the cord broke loose mid-race. Jerome instinctively grabbed hold of the flapping end and led David the rest of the way.
"I call Jerome my other son," says Francine, who watched from the stands. "I always know he's going to get David down the track."
Though Jerome works afternoons at a sporting goods store, the partners find time to hang out at the beach. They both love shopping and, before meets, pick out new shoes and warmup suits from a Nike outlet.
Given their personalities, there aren't many quiet moments as they argue like family and talk about the important things — music, cars and women.
"He's big brother," David says. "I'm little brother."
The world championships in Doha, Qatar, later this week represent another step in their burgeoning collaboration, the training that stretches year-round with few breaks. Next summer, they will be favored to win the 100 and 200 at the 2016 Paralympics in Rio de Janeiro.
A double gold — guides get medals, too — might require some technical fixes. David's lean to the side, though barely noticeable, prevents him from running straight ahead at top speed.
"He's looking for Jerome," Cruz says. "He's wasting time."
There is also the issue of the tether, which was eight inches long when they began sprinting together and has been cut in half, forcing them to run in tighter sync.
"As we get faster, it gets shorter," Jerome says. "There's less room for error."
Eventually, they hope to grow so accustomed to each other, communicating by touch and sound, that there is no need for artificial connection.
They want to run freely, side-by-side, and throw that tether away.
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