Thermal clothing giant Damart Sport has signed a major deal which aims to boost sporting performance.

The Bingley company, which has a £70 million turnover, has become an official clothes supplier to Leeds Tykes Rugby Union Club.

The announcement comes hard on the heels of the company revealing that it had signed up several athletes and sporting personalities to help it advertise products.

The Tykes will wear the firm's clothing in training and during pre-match warm-ups to help prevent muscle injuries.

Damart's clothes work by trapping layers of air, insulating the wearer, and keeping them warm. Hydrophobic properties in the fabric get rid of perspiration and moisture, meaning wearers do not get the cold, clammy feeling caused by exercise. The revolutionary clothing has been pioneered using experts from some of the nation's top sports clubs, including Rugby League World Club Champions Bradford Bulls.

The Bulls, who tested Damart Sport's products for two years, found the clothes made a difference to the level of injuries suffered.

Physiologists at the Bulls found the Damart fabric kept muscles at the optimum temperature for exercise, meaning they were kept warm and flexible.

Earlier this week the Telegraph & Argus revealed Damart had signed a deal with Bradford City to supply players with clothes.

The deal with the two sports clubs comes just weeks after the company officially launched the Damart Sport brand. John Bottomley, marketing director at Damart Sport, said: "We supply several of the country's top sports clubs."