Wu hasn't been able to recover from a bike crash three weeks ago and has reluctantly withdrawn from Sunday's Ironman 70.3 in Canberra, which has attracted more than 1200 competitors.

Wu will instead focus on January's Asia-Pacific Championship in Auckland in January, before switching her focus to the full Ironman distance at Port Macquarie's Australian Championship in May.

Wu made her Ironman debut - a 3.8-kilometre swim, 180km bike and marathon run - in Japan, in August, finishing runner-up.

Disappointed to miss Canberra's headline triathlon, Wu said she needed to focus on longer-term goals. ''It was touch-and-go, if I had another week it would have been fine to race Canberra,'' she said.

''I've been wanting to do this race all year because I don't get to race at home.

''The Ironman is where I want to end up, so I'll probably tackle a few more of them next year. Depending how things go, I'd like to aim for Kona.''

If she does make the lava fields of Kona, Wu is likely to toe the line with Bek Keat, the women's favourite for Sunday's race in Canberra.

Keat, 35, is in red-hot form and has broken course records for 70.3 races - the traditional half-Ironman distance - in Austin, Texas and Shepparton, Victoria in the past two months.

But Keat is also gearing up for her seventh assault on Hawaii, having led after the swim this year before a bike malfunction ended her race.

''I've never come out of the water in the lead pack, but for the first time in my life I came out of the water and I was actually first out of transition on the bike, I was leading the world championships,'' Keat said.

''I was thinking, 'this is unbelievable', it was a dream come true, I almost had tears in my eyes. I still haven't really performed to my potential there, I feel like my first year was my best year … I feel like I've still got a lot to do to satisfy my goals there.''

Keat broke the Ironman world record in Germany, in 2009, but even that was spoilt by four-time world champion Chrissie Wellington, who beat her across the line.

Keat trains on the Gold Coast with two-time Hawaii Ironman champion Mirinda Carfrae, who broke the race record on the way to winning the title this year.

Keat said triathletes such as Carfrae and Wellington had showed her there were no limits.

''It's weird for me to be breaking records at 35 when you've been in the sport for 15 years. But a few of the guys I've talked to at the top, like [three-time Hawaii winner] Craig Alexander have said 35-40 are the best years.''