The Chelsea & Westminster Health Charity London Duathlon is billed as the world's largest duathlon and takes place on Sunday September 14 2008 in Richmond Park.
The event requires participants to run and cycle for either 20 kilometres or 34 kilometes. The easier, "fun" option involves a 5k run, 10k cycle and 5k run, while the "challenge" race involves a 9k run, 20k cycle and then 5k run.
The Chelsea & Westminster Health Charity provides vital research, medical equipment and services for patients at the Chelsea & Westminster Hospital NHS Foundation Trust. It uses art to create a healing environment and encourages health and wellbeing through sports activities.
Diane Yeo, chief executive of Chelsea & Westminster Health Charity, said: "The Chelsea and Westminster Health Charity London Duathlon is the first step in the Charity's ambitious programme aimed at improving the health of the people of West and South London.
"Funds raised will go towards the CT Scanner Appeal and other deserving projects which do not have funding from the NHS."
The London Duathlon has previously been sponsored by sportswear brands Asics and Orca, Abbey Well water and The Independent newspaper.