FOR Ruse's Erin Densham, the fatigue usually comes after her 1500 metre swim, 40 kilometre bike ride and 10 kilometre run.
But on her biggest stage — the London Olympics in front of millions of people — that fatigue came early.
"I was just really, really tired before the race and something wasn't quite right," she said.
"Me and my coach have gone through the lead-up and tried to pin-point what went wrong, but we're not sure.
"I had headspins on the bike which is really unusual for me, and my run wasn't as strong as it can be, but I did all I could on the day."
As you might remember, during that tired old swim, cycle and run, she won a bronze medal for Australia.
Densham said she was amazed at how many people supported her from Campbelltown and is grateful to everyone who joined her family and friends to watch her race from Campbelltown Catholic Club.
"I'm very humbled by all the support I received and I hope they all had a drink for me," she said.
"I can't thank everyone individually, but I hope they know I appreciate it."
Leading into Saturday's Triathlon World Championship grand final in Auckland, Densham leads the championship by 30 points.
To win the world title she must beat rival Lisa Norden of Sweden — the London silver medallist.
"It's a good feeling to go into it leading but it will come down to who wins on the day, because it's so close," she said. "I'll do all I can."
She has won an under-23s world title, but never an open world title, which she had dreamed of since taking up triathlon with the Macarthur Triathlon Club as a teenager.
Considered an inspiration at her old stomping grounds of Ruse Public School and John Therry Catholic High School, Densham doesn't see it that way, however.
"It's kind of weird to think people are inspired by me," she said.
"I hope I'm a good role model for the kids at my former schools."
Old school friends from John Therry will head to New Zealand to hopefully see her win the world title she's spoken about for years.
But Densham won't get a chance to celebrate with them.
She is off to Hawaii the day after for another race where she hopes to become the Xterra off-road triathlon champion.