Athlete off starting blocks

The science of winning

Despite all technological gadgets and gizmos, sport is still about perspiration and inspiration.

It's got ultra-thin panels to reduce drag, stabilisers to offer support, and has been developed in association with Nasa.

No, it's not a new space module - but, the swimsuit that made waves in the lead up to the Beijing Olympics.

More than a dozen records in the pool have tumbled this year and many say that the Speedo LZR Racer is the cause.

The body-hugging suit is primarily designed to reduce the amount of drag swimmers create in the water thus allowing them to get the most from their strokes and kicks.

The suit has bonded seams so no stitching is showing, and thin panels over the chest area. There are core stabilisers above the hips to help support the abdominal region which suffers stress in the later stages of a race. The snug design stops muscle movement from causing extra drag.

Former Great Britain Olympic medallist Steve Parry attests that it feels like you have nothing on when you are wearing it, because it is so streamlined.

The LZR is the latest example of the impact sports engineering is having on a multi-billion pound industry. It highlights the role of UK scientists and the international cooperation in different engineering fields.

Researchers at the University of Nottingham helped test swimmers' bodies to see where the areas of high drag were, and Nasa then used fluid dynamics to model the impact of different fabrics.

Speedo had to work within rules laid down by the governing body, FINA (International Swimming Federation), which specifies that swimsuits should not have buoyancy aids and must be of a minimum thickness.

Unsurprisingly, the success of the LZR led to complaints from other manufacturers, and the governing body had to clarify its rules. The row showed how terms are sometimes failing to keep up with technology. Acording to FINA, a swimsuit should be made of a fabric, and much of the debate centred on whether the polyurethane, used on some of the panels on the suit, was legitimate.

This is no arcane dispute as the suit is set to go on sale to the general public for around £300 apiece. The knock-on effect of promoting the Speedo brand is worth millions.

Undoubtedly, the Speedo suit can help swimmers perform but is it really responsible for such a devastating series of records?

It was perhaps no surprise that records should be broken as athletes in all disciplines were nearing their peak as the summer Olympics approached.

There is also something of a placebo effect from having a new piece of equipment which can instil confidence in a sports person. This can lead to better performances. Whether the cause is the equipment, the confidence or a mixture of both can be difficult to assert.

Sums and science

The performance of top athletes in all disciplines is increasing by small, incremental steps. Any edge can make the difference.

But leaping ahead are the sums amateurs are prepared to pay for sports equipment and the general public - for sports apparel. These are the lucrative spin-off benefits from sports engineering.

At the University of Loughborough, renowned for its students' on-field prowess, a new £15m Sports Technology Institute opened earlier this year.

It was set up as a partnership between the East Midlands Development Agency, English Institute of Sport, UK Sport and Loughborough University's Innovative Manufacturing and Construction Research Centre
to boost enterprise in the sport and leisure sector and develop cutting-edge technology to support future British champions.

The university is already home to the Sports Technology Research Group which, over the last 20 years, has worked with some of the biggest names in the sporting goods industry including Adidas, Head, Umbro, Nike, Reebok, Speedo and Dunlop Slazenger. Recent high profile projects include partnering Adidas in the development of their revolutionary 2006 World Cup and Euro 2008 footballs.

It's clear that this new technology institute is looking for success on the high street as much as on the athletic track.

Six million pounds have been ploughed into specialist facilities for the design, simulation, testing and manufacture of sports equipment, footwear and apparel.

Professor Mike Caine, director of the institute says: "This new facility will enable us to develop cutting-edge training equipment, coaching aids and customised clothing and footwear to support the country's elite athletes and sports governing bodies. It also provides a perfect vehicle to foster longer-term innovation in a broader range of sports and active pursuits."

Another key research venue in the UK is the Centre for Sport and Exercise Science at Sheffield Hallam University.

Opened eight years ago, it is led by Professor Steve Haake, an internationally recognised expert in sports engineering.

The centre carries out its own research as well as consultancy on behalf of the private sector and was supporting British athletes as they prepared for the Olympics.

Among the research areas are high-speed videogrammetry in golf, tennis and football, simulations of sports ball impacts, computational fluid dynamics and movement analysis.

For instance, its scientists are currently modelling the impact of a tennis ball on a racket so that they can simulate what would happen should different physical properties, such as string friction, change.

The latest developments were on show at the bi-annual conference of the International Sports Engineering Association in Biarritz at the beginning of June.

More than 150 scientists attended, and the prospect of seeing some of their research put to the ultimate test in Beijing had made this event keenly anticipated.

Boots, balls and poles

Some sports, however, get more attention than others.

Two areas where companies are investing a lot of research are boots and balls. The reason is simple: economics. Football and tennis are played by millions of people, so the potential market is huge. There are also plenty of places to test and advertise new equipment.

You can see the impact of technology in football in the nature of the ball. Every tournament seems to spark concerns about balls which dip or swerve unpredictably. They may make games more interesting. Such deviations are minimal, though, compared to the role of improved coatings on footballs to reduce their water retention and to make sure they maintain their size and weight.

If you look at some Olympic sports with a long history, the impact of technology is mixed.

In pole vaulting there is no restriction on the length of pole or the material it is made from. They just have to be smooth.

The stress factors on a pole mean it does not have to be solid, that is why light and flexible bamboo was popular. The advent of fibreglass gave pole vaulters a sudden extra lift because such poles could be bent and sprung by athletes far more than bamboo versions.

In the javelin, by contrast, throwers were getting so good they were almost clearing stadiums, so there are strict rules on the weight, length and centre of mass. Using the simple expedient of moving the centre of gravity forwards, javelins now fly less far and land tip first.

The 100m sprint is the centrepiece for any Olympics. Indeed, a sprint, albeit over twice the distance, was the first recorded event of the original Olympic Games.

The Greeks changed the start to make sure it was fairer, first by having a line marked out for athletes to put their feet on and then, by using starting cages. Since then, the major developments have focused on better running shoes and tracks. The improved coaching and diets, however, have probably had a greater impact than any technological innovation.

What is really different stays off the track. The value of the winning athlete wearing your company's training shoe is immense, and sports engineering is as much about refining the design and production of these valuable pieces of equipment for mass consumption as shaving tenths of a second off world records.

Theory and practice

Watching Roger Federer hit a sweet volley or David Beckham's curling free kick is one thing - recreating them is another.

One of the biggest challenges facing sports technology is understanding exactly how top sportsmen achieve their feats.

A lot of effort goes into developing the sensors necessary to gather raw data before the scientists can start to recreate the winning action.

For instance, basic physics should tell you that the optimum angle, relative to the horizontal for releasing an object, like a shot putt, is 45°. However, if you study shot putters in action, it is less than that.

Nick Linthorne, a sports science researcher from Brunel University, studied tapes of athletes to find out the optimum angles for different sports that relied on people throwing things.

For a shot putter 32-35°, a long jumper is between 20 and 25°, and a javelin is released at about 37°. For a footballer, an optimum-distance throw-in angle is around 30°.

According to Linthorne, the reason for the disparity lies in the biomechanical structure of the human body.

The lower launch angle works best because the arrangement of muscle levers in the arms and back allows you to exert more throwing force in the horizontal direction than vertically.

Creating a spin

So physics gives you a start, but there are numerous other factors to take into account.

Similarly, scientists have spent many hours studying how sportsmen create spin, dip and swerve of a ball.

The theory can be traced back to Gustav Magnus, a 19th century German physicist interested in why spinning shells and bullets deflected to one side.

If a ball is spinning perpendicular to the flow of air across it, then the air travels faster relative to the centre of the ball as the periphery of the ball is moving in the same direction as the airflow. According to Bernouilli's principle, this reduces the pressure.

However, the opposite happens on the other side of the ball, and this imbalance causes it to deflect. This lateral deflection is generally known as the Magnus effect.

Other factors, which can influence this swerve, include surface roughness, wind conditions, how wet the ball is and how fast the ball is travelling.

The interesting thing is the last variable because swerve increases as the speed drops due to a change in the drag force. A top footballer needs to judge the force necessary, so that the speed drops when the swerve is needed to take it around a wall and into the net. This is something footballers learn through hours of practice.

Sports scientists and engineers have to spend a lot of time modelling the complex physical motion of the human body. They need to take into account a huge number of variables: from the weather conditions to the footwear and the pressure inside a ball.

Which, thankfully, means sport is still about perspiration and inspiration rather than just creating a magic boot.

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