Greg Stolz | The Courier-Mail | Pic above: Adam Head - As if top-level paddling is not tough enough, Wallace will this week put his body through the five-day torture test that is the Mark Webber Challenge adventure race in Tasmania.

The 350km epic, founded by Australian Formula One racing ace Webber as a charity fundraiser, will involve a punishing six to eight hours every day of different disciplines comprising kayaking, mountain biking, running, swimming, orienteering and abseiling through some of Tassie's wildest terrain.

Wallace, a Gold Coast lifeguard who won gold in the K-1 500 at the 2008 Beijing Olympics, was a spectator at last year's Mark Webber Challenge after being invited as a guest by the F1 star.

The experience whet his competitive appetite and he decided to have a crack at the event himself.

After the disappointment of finishing fourth in the K-2 1000 final at this year's London Olympics, Wallace is using adventure racing as a "break" from kayaking.

"After four years of being focused on London, it's good to have a break," he said yesterday.

"A lot of people have a complete break after the Olympics and do nothing at all, but I just love that feeling of being healthy and fit. The mental side of pushing my body for six to eight hours a day is also a good challenge."

Wallace, 29, is still doing his kayak training five days a week but has added cycling, running and swimming to his schedule.

"I'm doing a lot of training but I'm enjoying it," he said.

"My wallet isn't though. I spent $270 on food last week. I'm eating the house down."

Wallace paired up with top triathlete Courtney Atkinson to form an elite team in the Challenge only to have his partner break his wrist in a mountain-biking accident.

Atkinson will still compete this week but the pair have brought in Gold Coast orienteering specialist Gary Sutherland to form a three-man team in the "enthusiasts" category.

Event website: www.markwebbertasmaniachallenge.com

Website Ken Wallace: http://kenwallace.com.au