A flying Emma Snowsill used anger to turn the tables on countrywoman Emma Moffatt and collect $A236,000 as she won triathlon's richest race for a second time.

Olympic champion Snowsill showed she was returning to her imperious best after almost a year out for hip surgery and a virus as she overcame a slow start to triumph against most of the world's best in the ITU Elite Cup in Des Moines, Iowa.

Last year, 25-year-old fellow Queenslander Moffatt held off Snowsill, the 2008 champion, to win the event.

In just the second race of her comeback, Snowsill was not settling for second best again as she stormed home on Sunday to win by 16 seconds from Moffatt, who just edged out Britain's Helen Jenkins for the $A59,000 second prize.

After struggling in the opening swim leg, the diminutive Snowsill was still a full minute down on the leaders coming off the bike and starting the final 10km run.

But she scorched to catch the pacesetters including Moffatt, Jenkins, New Zealand's Andrea Hewitt and Great Britain's Jodie Stimpson before the 7km mark and draw away.

"I was a bit angry with myself because in the first lap of the swim I got annihilated," said Snowsill, who turns 29 on Tuesday.

"Maybe I have to use my elbows a bit more, or maybe it just took me a while to get back into race mode because I was certainly off the pace at the start.

"I used that anger on the bike and tried to make amends for a poor start and for the disappointment of last year's race here.

"A lot has happened over the past 12 months and a lot has changed, so it was a matter of bottling that up and using it as energy.

We did get a bit of time back on the leaders at one stage on the bike, but I was still pretty worried at the start of the run when I heard I was so far back."

Moffatt, who has taken bronze medals in tight sprint finishes in the two world championship races she has contested this season, was pleased enough with her performance.

"It's always good to be in the front pack on the bike but I don't think we made the most of it and could have organised ourselves a bit better to put some more time on the rest of the girls," she said.

"On the run, there were two u-turns on every lap so I could see Emma coming through the field pretty fast and there were also some good runners around me, so there was enough to worry about.

"Once Snowy caught me I tried to go with her, but that little campaign didn't last long because she was absolutely flying."

In the men's race, Great Britain's Tim Don emerged from the pack with a standout run to win by four seconds after the entire field was glued together for most of the 40km journey on the bike.

New Zealand's Kris Gemmell took silver, while Australia's Courtney Atkinson continued his outstanding form to claim bronze a further four seconds back.

Going into the run Australian duo Atkinson and Brad Kahlefeldt, Olympic champion Germany's Jan Frodeno, Kiwi veterans Gemmell and Bevan Docherty and last year's winner Canadian Simon Whitfield were all in the mix at the front.

Atkinson has won silver medals in the past two ITU world championship races and picked up $US25,000 ($A30,000) for his efforts in this race.

AAP