MACK Horton admits the intensity heading into his Rio Olympic campaign was "nuts" and he had to pull back if he was to make it through another four-year cycle to Tokyo in 2020.
Horton sealed a third consecutive national 400m title in Brisbane in his first major meet since winning gold in Rio last year.
Horton beat Rio teammate David McKeon by just over a second, touching the wall in 3min 44.18sec, well outside his Olympic final time but still the second best in the world this year behind Italian Gabrele Detti's 3:43.36.
Horton said his sole aim heading into nationals was to qualify for the world championship team, something he did on Sunday night.
"You've got to pull back after Rio because the intensity leading into the Olympics was nuts,'' he said.
"My attitude's pretty relaxed all around to be honest.
"I'm obviously still training pretty hard but usually we set goals around skills and they're constantly on my case about everything and we haven't really been doing that for the last couple of months because there's three years (until the next Olympics) still.
"I'm just enjoying swimming and training and not being too crazy."
But Horton admitted he was more nervous than he thought he would be heading into last night's final and was glad to have earnt his ticket to Hungary for July's world titles.
"I was a bit more nervous than I thought I was going to be because I didn't know where I was going to be (in my preparation) and I wanted to be on that team,'' he said.
Cameron McEvoy won the 50m freestyle in 21.55sec, the fastest time in the world this year.
After setting a world-leading mark of 21.73 in the heat yesterday morning, McEvoy bettered that mark in the final, just outside his personal best time.
"That's pretty special and good practice for the Commonwealth Games next year,'' he said of racing in front of a vocal home crowd.
It was a Gold Coast one-two, with Somerset swimmer James Roberts touching just behind in 21.91.
"It was my second-quickest ever, 0.11sec off last year, 0.25sec quicker than Rio, that's pretty cool,'' he said.
"And not 100 per cent (tapered) ... so 21.5 is pretty exciting.
"I can fault it in quite a few ways which is exciting, it's a great kickstart to the week.
"I'm happy to know that that's where I stand."
And McEvoy said the effort boded well for his pet 100m and 200m events later in the week.
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