Tim Brabants, who won a gold and a bronze for kayaking at the Beijing Olympics last year, will row in a men’s four crew for the race on 4 July.
The former doctor at the General Hospital is aiming to finish the 19-mile challenge in under two hours.
Brabants worked at the Hospital from August 2005 to February 2006 before he left to concentrate on his sporting career. He will race alongside friend and former Jersey colleague, Dr Carl Clinton, who suggested taking part in the event.