Swimming: Science gives stars turbo-boost

By PETER JESSUP

Ian Thorpe can swim even faster, Keiren Perkins should win the 1500m freestyle final on Saturday and people such as sprinter Alexander Popov should get bodysuits.

How do we know?

The IOC yesterday revealed that it is conducting medical and biomechanics research to monitor the start, stroke, turn and finish of all top-16 competitors, feeding the data straight back to team coaches, whose athletes use it to break world records.

The Russians started work in the area in the 1980s, Australia is perfecting it, and the IOC has now pulled an international team together to watch every movement in the pool and make the research finding immediately available to team coaches.

Professor Bruce Elliot, head of the department of human movement and exercise science at the University of West Australia, says coaches get a spreadsheet explanation of who won and why, and who lost and why.

Australian coach Don Talbot has used it to good effect. Thorpe's personal coach, Doug Frost, gets annoyed when results are not supplied quickly enough to allow the pair to re-evaluate their strategy between heats and finals.

Elliot said the science team record stroke length, frequency, velocity through the water and turn times.

They also measure consistency in performance. As Thorpe swims, his action is compared to a computer-generated model of a perfect stroke to show where he needs to improve.

But Thorpe's stroke is already almost perfect, says Elliot.

"Almost all swimmers are inefficient in some area which results in them having to use a higher stroke rate. Thorpe gets propulsion from every bit of the stroke so he strokes more slowly and stays in front. When challenged he has the capacity to increase his stroke."

Swimmers are getting taller and Thorpe, who can sit in the middle of the back seat of a Commodore and open both back doors then flap them like ears, has a distinct advantage.

His big feet help, too, says Elliot.

Most swimmers gain 85 per cent of their velocity from arm stroke and 15 per cent from their feet; Thorpe is an exception - 17 per cent from his size-17s.

The data also shows that the world-record-setting Dutchman Pieter van den Hoogenband can swim faster.

The information comes from seven in-pool cameras, nicknamed Mobycams.

The IOC had initially decided the swimmers should not be allowed access to the data in Olympic competition because Australia and others who used it, including the United States and New Zealand, would have an unfair advantage. But the researchers have made it available to all countries and 140 at the Games have asked for it.

Bruce Mason, of the Otago University medical school, is part of the team. His speciality is the change in performance between heats and finals, the efficiency index between stroke length and frequency.

As for the new sharkskin suits, there are too many variables to determine their impact.

At the United States swim team altitude training camp in Colorado, testing showed a 6 per cent decrease in drag and a 0.74 per cent gain in velocity when suits were worn.

But the swimmers who did not wear them in the tests were not shaved as they are for competition; the team have tested only the full neck-to-ankle suits, and not the range athletes are now using; it is not known yet what effect, if any, the suits have in the turns.

The initial conclusions from video analysis is that the "fast" Homebush pool, with its chemical mix based on ozone instead of chlorine, helps the suit wearers. Ozone bubbles are held in the dimpled skin, adding buoyancy. Devices or swimwear that increase buoyancy are prohibited under the rules set by the international governing body, Fina, but the organisation has already decided the suits do not add buoyancy.

Jean Claude Chatard, from French university St Etiennes, is looking at how the data can be used to determine competition strategy. Currently, most swimmers go out with a plan then abandon it in the heat of battle, he says. He can show them why they should not. "Petria Thomas started fast and came second to Susie O'Neill who started slower."

Spaniard Raoul Arayano is breaking down the data to work out which areas of technique offer the most gain, and which should therefore be worked on.

Elliot says the teams do not supply much feedback on how they use the data and what effects there are.

But the system has undoubtedly added a dimension to coaching and performance because there is clear demand for it.

Many Australian swimmers were going out too fast and until recently, coaches had only split times to work from. Now they have a metre-by-metre analysis.