A new trainer invention has been proposed as the answer to knee injuries among netball, basketball and tennis players.

The shoe, which is called, Rotasole, was invented by Australian doctor Jack Goldberg and his son Brian who believe the footwear could provide a revolutionary way to protect sports players' knees.

The trainer contains a flat rubber disc in the ball of the sole, which swivels every time the wearer turns or pivots to allow easier movement.

Brian Goldberg, Rotasole's chief executive, said: "It makes sense that if you are twisting and pivoting during the sports, such as basketball, tennis and netball, then the shoe should provide support for these strenuous movements. Rotasole provides this turning support."

The invention has been nominated for the Victorian Australian Technology Showcase Patrons Award, which could lead to an award of A$40,000 should the Goldberg's design succeed.

Rotasole is expected to go on sale in Australian sports stores and sports clubs over the next two months.

However, the Goldbergs hope to eventually market the footwear to a much wider international market.