They stretched and shook their limbs behind the starting blocks, the relaxing shimmy before the 50-second explosion.

Among them: Sanya Richards-Ross of the United States, the 2008 Olympic bronze medalist; Novlene Williams-Mills of Jamaica, a top talent from a country that produces world-class runners the way Stanford produces computer programmers; and Amantle Montsho, the reigning world champion.

Montsho (29) is from a rural village in Botswana, a country not known for elite athletes.

She trains in near isolation in Dakar, Senegal, working day after day to refine her technique in the name of winning races, most important the one this summer at the Olympics in London. She is the first female professional athlete in the country, which has not won an Olympic medal in any sport.

What, exactly, is it that makes a runner like Montsho excel at the 400?  Montsho and her peers come from starkly different backgrounds representing a variety of cultures, personal experiences and training regimens.

But once the starting gun was fired at the Prefontaine Classic here in June, they remained in near lock step over 400m, separated at the finish line by fractions of a second.

The 400 is “the most unique race,” said Thomas Best, a professor of family medicine and a co-director of sports medicine at Ohio State University.

“The reason is that you are activating all the energy systems and energy pathways known to man. Therein lies the real challenge.”

When a runner like Montsho settles into the starting blocks, she looks “like a quadrupedal animal,” said Stephen Simons, the team physician for Notre Dame University track and field.

“They’re leaned over, hands on the track, butt up in the air,” he said. “The shoulders are over the hands, the elbows aren’t locked. Body weight is evenly spread to feet and hands. The back is flat, and the lower leg is at a 45-degree angle.”

With the bang of the gun, the eight women were off, Montsho in Lane 3, Richards-Ross to her right in Lane 4.

“You’ll have that explosive reaction,” Simons said. “The starting posture with the gluteal muscles up high pulls the femur back, putting a premium on the gluteal muscles for the first quarter of the race, especially as they start out of the blocks.”

The start is considered a transition, with runners not yet reaching their full speeds until their torsos rise to become perpendicular with the track.

Montsho considers herself a slow starter and a strong finisher.

That runs counter to many of her competitors, who may have more experience running the 100 and the 200 and struggle for the extra push toward the finish line of the 400.

For months at a training facility in Dakar, Montsho’s coach, Anthony Koffi, had her run starting drills, aimed at shortening her response time. During one practice, Koffi had his runners line up behind the starting line. He held two pens behind his back. If he held up the yellow one, the runners were to start. If he held up a blue pen and they started, they had to do 20 push-ups.

He held up his hand — with no pens — and a few runners, but not Montsho, jolted forward. She laughed. He held up the yellow pen and she triggered forward.

Then he held up both pens at the same time. All the runners sprang forward. “No!” Koffi said. Just the yellow! They all laughed, then retreated to their starting positions. “You must concentrate!” he yelled.

“The games help us,” Montsho said.  Any shortcomings in her starts are certainly not a result of her body type.  In 2005, Peter Weyand, an Associate Professor of Applied Physiology and Biomechanics at Southern Methodist University in Dallas, examined the height and weight ratios of elite sprinters.

Using data over 15 years for the top 15 performers in the event, Weyand found that for female 400-meter runners, the average was 5 feet 8 inches and 127 pounds.

Montsho is about 5-9 and 134 pounds.



> Heart of the Race

By the middle 200 meters of the race, runners are upright, their arms and legs churning to propel them. This is usually the part of the race when runners reach their peak speed, as bodies are warmed up but not yet fatigued.

Montsho and Richards-Ross appeared to be in the lead as they rounded toward bleachers packed with fans.

“You don’t want to feel like you’re working the second 200 meters,” said Ralph Mann, a silver medalist in the 1972 Munich Games in the 400m hurdles who has a PhD in Biomechanics and works as director of USA Track & Field elite sprints and hurdles.

Most runners begin to break down around the 250 to 300m mark. Tapping the body’s anaerobic system, which provides power and strength in short bursts, for an extended period causes the release of lactic acid — and an intense feeling of fatigue.  Still, 100 meters remain. By now, some 30 to 45 seconds have passed and many runners feel excruciating pain. The quadriceps are usually the muscles that fail the most during the last 100m , but all muscles, including those of the gluteus and hamstrings, may feel like they’re failing, too.

“It’s such a crazy race,” said LaShawn Merritt, the reigning Olympic champion in the men’s race. Although he has extraordinary muscular strength that powers him through the first 200 metres — sometimes in less than 20 seconds — those muscles may also suffer under a buildup of lactic acid toward the end of the race.

“A lot of people can’t handle that lactic acid,” Merritt said. “When that lactic acid hits, naturally, your body wants to do something. “Naturally, your body wants to rock back, your legs want to flare up, your arms, your body is just in this shock mode and you really have to get in the mental zone and focus on just moving forward.”

Proper fuel can help here.

Female sprinters at this level commonly consume 3 000 calories or more on training days, with about 60 percent coming from carbohydrates, said Liz Applegate, the director of sports nutrition at the University of California.

Montsho says she does not care for the food she is served in Senegal — mostly meats and vegetables over rice. She longs for the sorghum porridge of her home country. “I think I would run better if I ate food from Botswana,” she said.

When she travels, she carries muesli that she picks up when she is home in Botswana, and she drinks purified water.

At meets, she will eat whatever food is provided, which often means a meal with protein and carbohydrates a couple of hours before the race.

Some runners do not follow the recommended diet and are no match for the intensity of the race.

“Four hundred metre runners are notorious for throwing up,” Applegate said.



> Relaxation

Toward the finish line, the upper body helps carry the runners through their final push.

But this is also where the distinction between sprinters and distance runners becomes clear. Montsho’s arms shred the air, her legs still pumping high with each kick.

A physical distinction between sprinters and distance runners is seen in their ratios of fast- to slow-twitch muscle fibres.

On average, most people have equal amounts of each. Those who are genetically prone to be sprinters have more fast-twitch fibres, and those better suited to distance running have more slow-twitch fibres. The difference yields strikingly different results on the track, coaches and scientists say.

Fast-twitch fibres generate quick pops of energy, ideal for a sprinter, but they fatigue more quickly. Slow-twitch fibres can endure.

“They’re approaching the finish line and need one last surge, and they literally cannot do it because they’re right on that edge and completely paralysed,” said Simons, the team physician at Notre Dame.

It is here that relaxation, perhaps counter-intuitively, can help win the race.

Michael Joyner, a physiologist at the Mayo Clinic, said that runners who tensed up, especially in the arms, moved more slowly. It is known as a “bear jumping on your back” or “turning to stone”.

The tension makes a runner less efficient biomechanically; she expends the same amount of energy but does not travel as far.

Some coaches and doctors, including Joyner, instruct runners to let their eyes droop during a race, hoping that if they relax their face, the rest of the body will follow.

“If you look at her face when she finishes, her face is super relaxed,” Joyner said about Montsho.

 “She’s not tightening up her jaw, and that’s very helpful.”  Part of relaxation is rhythm. Koffi, Montsho’s coach, has her jump rope and run up staircases at least once a week. Hurdles and high-knee exercises, like those pioneered by Winter, are also a mainstay.

Koffi also believes in using humour during practice, often yelping as he cheers runners up the stadium staircases.

“They need to laugh,” he said. “They need to relax.”

Koffi’s methods of measurement are far from precise.

Occasionally, he counts Montsho’s strides in a race, but he spends more time concentrating on Montsho’s strength in the weight room and form on the track, critiquing her stride more in the manner of a ballet coach.

When reviewing video with Montsho, he makes comments on the height of her knees, the chop of her arms, the relaxation of her face. If her form is good, she will complete the race in fewer, wider strides, he said.

Thirty-five seconds into the race, Montsho was the leader.

She rounded the second curve of the track into the homestretch. Then Richards-Ross surged. At 44 seconds, the two ran shoulder to shoulder.

As they neared the finish line, their faces told the story. Richards-Ross was at ease, even smiling, as she edged past Montsho and broke the tape in 49.39 seconds. Montsho’s face was a portrait of strain and pain. She finished second, in 49.62.

“I won’t change anything,” she said of her training and technique heading into the Olympics. “I just have to improve my speed.

“You have to run with your whole body.”

Excerpted from the New York Times.