Sprint finish

This summer, all eyes were on one man. When Usain Bolt performed his rituals before taking his marks for the 100m at London 2012, the world was watching to see if he could keep his cool and leave the other competitors in his wake, as he has done so many times before. Despite all the speculation about his fitness, Bolt won the race and clocked the second fastest time in history.

In the months leading up to the Olympic Games, much was written about the aptly named Bolt – his entourage, the sponsorship deals and the way he prepares for competitions after famously admitting he likes to eat chicken nuggets. But one thing that many people would like to know, most of all his rivals, is what makes him so successful? Is it genetics, training, attitude or a combination of these things, plus a little luck?

Professor Alan Nevill is a specialist in biostatistics applied to health, sport and exercise sciences. One of his recent research projects has involved looking into the changing body shape of sprinters, and how shapes have evolved over time.

His findings are very interesting, particularly when you look at the success of sprinters such as Usain Bolt.

“World-class 100m sprinters offer the purest expression of human speed, with considerable kudos associated with the accolade of being the fastest man or woman on the planet.

“Over the last ten years, sprinters have become leaner, more linear and less bulky. Usain Bolt is a good example of this, as is the European 100m Champion, French sprinter Christophe Lemaitre, who clinched gold in Helsinki earlier this summer,” he says.

“Up until 2001, sprinters were still these bulkier, more powerful runners. But British Olympic gold medallist Linford Christie was beginning to shape the mould, with a more elegant body shape.”

Is it the same for female runners? Professor Nevill explains that women have always tended to be taller, leaner individuals.

“Two good examples are German athletes Heike Drechsler and Katrin Krabbe. They were both very elegant, very tall and very lean. They were outstanding runners and Drechsler excelled at long jump as well.”

Characteristics of success

The research, titled The changing shape of success in world-class sprinters, was published in the Journal of Sports Sciences. Carried out with Wolverhampton colleagues Adam Watts and Dr Iain Coleman, it sought to identify whether relative shape and size characteristics of world-class sprinters have changed over time, and what characterises the most successful world-class sprinters.

The data used was the body size (height and weight) and sprint time for 100m for both men and women in the top ten 100m world list of best performers. The researchers looked at ten decades (1910-2009) for men and eight decades (1940-2010) for women.

From the athlete’s height and weight, the researchers were able to calculate their body mass index (BMI) and reciprocal ponderal index (RPI).

Professor Nevill, who is from the School of Sport, Performing Arts and Leisure, explains: “While BMI is an important factor associated with success in both male and female worldclass sprinters that may suggest the influence of muscle mass on sprint performance, the RPI has emerged as a more significant factor in success, with taller, linear sprinters - like Usain Bolt, for example - achieving greater success as measured by sprint speed.”

But why might this be? Is it that over time, this has evolved as a more effective body shape or is it something else?

“I think it is something to do with stride length,” he says. “The sprinters with the leaner, more linear body shapes are gaining advantage towards the second part of the race. They can keep up with the more powerful, bulky runners who get the explosive starts and then have a longer stride after about 40-50 metres. I believe the longer stride is showing benefit in the latter part of the race.”

Momentous records

Breaking the 100m world record is always a momentous occasion, gaining the athlete a place in history. Professor Nevill provides some interesting insights into whether the records that exist today will be broken.

“I’m not convinced sprinters have reached their peak. They continue to evolve and there is some evidence they could go even faster.

“But in events such as the 1500m or 5000m, I don’t know if they can go much faster than at the present really. However, it is worth noting that you could get a freak situation where all the conditions are right.

“Another factor could be if they started measuring to a third decimal place in the sprint events, so instead of 9.67 it could be 9.676. If that was to happen, then you could get new world records.”

Moving forward, what could the research findings mean for competitors? Professor Nevill has some thoughts.

“The results suggest that coaches, selectors and sports scientists should consider body shape when selecting potential athletes for sprint events, encouraging more linear athletes with a high RPI.”

With an audience of millions around the world, the 100 metres final is always a momentous occasion during the Olympic Games.

It is interesting to know that alongside years of physical and mental training, a nutrition-packed diet, determination and a pinch of luck, body shape is a significant factor in who clinches that coveted gold medal.