Sir Steve Redgrave, the five-time Olympic rowing gold medallist, has been appointed to help promote sports participation as part of legacy plans for the 2012 London Games.

Redgrave has been named by the government as its 2012 Sports Champion, which will see the former Olympian supported advise ministers and national governing bodies for sport to boost participation across all age groups. Six Olympic and Paralympic medallists - currently working as School Sport Ambassadors through the Youth Sport Trust - will support Redgrave's work, including Darren Campbell, Denise Lewis and Gail Emms.

It is expected that Redgrave will help the government build on existing work to increase participation levels across the country, including the £140m free swimming initiative and an overhaul of delivery structures. Redgrave said: "2012 is a once-in-a-lifetime chance to change the habits of a nation and get across to everyone why sport and physical activity matters. This is a great responsibility but a great opportunity as well.

"I want to work with those who have the task of making sure the benefits happen from hosting the Olympics and Paralympics but I won't be afraid to ruffle feathers if I need to. A lot of good work has already been done - but there is no time to lose." Culture secretary Ben Bradshaw added: "Steve Redgrave, working with our six School Sport Ambassadors, will champion the cause of getting more people playing sport as one of the key long-term benefits from hosting the Olympics and Paralympics - and challenge us to make sure that we achieve this."

Redgrave will also serve on a new legacy delivery board, which aims to help achieve the government's target of getting 1 million more adults playing sport and ensuring young people have access to five hours of sport each week.