In the water at the beginning of his first world event - his first time representing his home country - the lesson was clear: get ready to be swum over.
“The second the blower went, some pretty big guys came charging over the top of me,” she said.
“Everyone was trying to get for position, so it took until the first buoy or so for me to really adapt to where I was and get into a rhythm.”
While Walker had qualified for the event after a strong season in 2018/19, the world event was not only a debut on the international stage for Walker, but also the first event of the new triathlon season.
And the return to competition presented its own set of challenges.
“It's daunting in comparison to your training,” he said.
“Adrenaline will overtake you at times, so you can easily go harder than you want to in the early stages of the race. It becomes a challenge of gauging where you are at and what you have to do to get into the best possible position.”
While Walker gained his rhythm, he admits his swim leg was far from his best, and after after a long transition leg for all competitors, entered the bike ride with a time slightly north of 15 minutes.
“You were nice and warm by the time you got on the bike,” he said.
“I gained a few seconds during transition on people. It's something I always try and produce well at.”
Using a borrowed bike better suited to the event than his own, Walker began to make his move on two wheels.
“I was back in 38th when he got onto the track, so I had that in the back of my head,” he said.
“I knew I had to put in a fair bit of work to make some ground on people. We had two hills to take on, including some pretty sharp bends at the bottom where a few people fell off.
“I had to be a bit mindful of that, also getting used to overtaking on a different side in comparison to Australian rules.
“I was able to make up about 20 places on the bike leg. I worked hard and as we were going through I was starting to pick off a few of the other age classes.”
Competing under draft legal rules - where riders can sit behind a leader in a group, allowing the front person to break the wind - it was a new challenge for Walker.
But he would be able to produce the 17th fastest time on the bike leg at 30:56, and after another two minutes on transition was ready to steam home on the run leg.
“I was really strong for the first two kilometres,” he said.
“We had some hills around the Olympic museum that blew my heart rate right up, and it was tough to get it back down.
“I played with a bit of tactics around the hills, so once I was able to get back onto the flats I was able to really push.
“I was about a minute off top 10, I think I would have been a bit quicker on a flat course.”
Though Walker may have been hunting a better time, he was far from under-performing.
He crossed the line in 1.07:37, the sixteenth fastest in the world for the 40-44 age category, but the second fastest time of any Australian in the category.
“When I first started training, I aimed for top 20,” he said.
“It was big ask, but as every week rolled on I was feeling pretty good about myself. I felt like I was about third fastest of the Australians, but was lucky enough to push into second. Being 16th in the world is an incredible feeling.”
But he's far from done.
“The worlds are in Canada in twelve months, so I have an eye set on getting back there,” he said.
“I'm pretty inspired to go again and push to get into the top 10 next time, so I have set myself that goal.”
13°C