Athletes move smartly in cool suit

A tracksuit containing a sweat-activated muscle-cooling gel could help athletes break world records in the 2004 Olympic Games.

The basis of the suit is a powder that changes into a gel on contact with an athlete’s sweat. It could slice vital seconds from running times according to its developer Dr Ji-Young Ruckman of Manchester Metropolitan University.

In events such as the 100m, the difference between a good race and a world record can be a hundredth of a second.

Heat stress in muscles can reduce a sprinter’s performance and research has shown that a drop in temperature of 1 to 2 degrees C can lead to a 10 to 20 per cent improvement in muscle power. To achieve this, clothing packed with ice is often placed around the athlete’s arms and legs before a race, but this is bulky and soon melts.

The gel suit, which is to be manufactured by an unnamed sports company and should be available for the Athens Olympics, is cheaper and lighter than these ice-based alternatives and does not melt, said Ruckman.

The powder, contained in removable pads, is known as a phase change material. These materials can switch from a solid to a liquid and back again simply by a change in temperature.

‘The suit has three layers,’ said Ruckman. ‘The inner layer has the ability to absorb water very easily, so the sweat passes through it. The heat from the athlete’s muscles and sweat activates the powder causing it to change to a gel. Finally the third, outer layer is designed to retain heat to help the powder maintain its state. The gel also has a very low melting point.’

In tests in a temperature-controlled chamber, thigh muscles covered in the material for 10 minutes experienced a 5 degrees C drop in temperature, which lasted for up to 20 minutes.