Women find their feet and roll with it

Aimee Olsen has been injured many times, but the thrill is irresistible "because it's a high-adrenaline sport," says one of the South African women who have become hooked on roller derby.

Fast-paced and aggressive, the contact sport provides a welcome bout of stress release for women players who say it's an addictive exercise far better than any gym.

During a twice-weekly practice session at a sports hall in Johannesburg's southern suburb of Turffontein, players sporting brightly-coloured crash helmets and protective elbow, knee and mouth guards speed around a concrete floor barging into each other.