Nobody ever doubted her ability to go fast and evidently, that hasn't been lost during her 12 months of relative inactivity in the wake of her individual Rio disappointments.

At the Australian Short Course Championships, springboarding from just six weeks of full-time training, Campbell would waste little time in reminding the swimming world that she's anything but a spent force.

The 25-year-old from Brisbane broke the 100-metre freestyle world record when she touched the wall in 50.25 seconds in Adelaide, which was 0.33s faster than her great Swedish rival Sarah Sjostrom, who had only lowered the mark in August.

It was the clearest of signs that Campbell still has claims to being the best women's sprinter in the world. But she knows that times don't always equate to victory. And it wasn't her capabilities in the water that she questioned the most when she was reflecting on her future.

What she really wanted to uncover was whether she could again dedicate her life to the pool, as she had done for her entire adult life leading into the 2016 Olympic Games. She returned with relay gold but nothing to show in her pet 100-metre and 50-metre events.

It made her wonder how best to perform at the big events and once she decided to go chips-in for Tokyo, she set about finding a mental approach that released the pressure without sacrificing performance.

Perspective outside of the pool seems to have helped. But so has the rise and rise of Sjostrom, who was one of the swimmers to console Campbell in the water in Rio when she looked up to see her dreams shattered.

Sjostrom not only owned the short course mark but lowered Campbell's long-course 100-metre freestyle record at this year's FINA World Championships in Hungary.

Prior to that, Campbell could easily have looked back at the Olympic final and reasoned that if she had swum her fastest, she would have won. Now, with Sjostrom's brilliance breaking new ground for all of the leading women's sprinters, Campbell has new territory to conquer.

"Sarah is swimming incredibly fast and watching her in Budapest, I was very pleased I didn't have to get up on the blocks and race her then," Campbell said.

"I am feeling a little bit better about the possibility about racing her in the near future. She broke this world record just a couple of months ago and I was in that race.

"When I breathed I remember seeing her feet and that was a little demoralising but very motivating at the same time. I have been very motivated to give 100 per cent because I don't feel like I am done with it yet."

Campbell's surprise record represents an early boost to her confidence on the comeback trail. But with records comes pressure, something she feels far better equipped to deal with now she has stopped being obsessive about her swimming.

"I am starting to learn how to keep a cool head on the blocks again," Campbell said in Adelaide.

Bigger tests await at the national trials in February, then the Commonwealth Games in April, where she meets Olympic champion Penny Oleksiak from Canada. But the early signs suggest Campbell will plot the road to Tokyo as a swimmer ready to take her opportunities, not one defined by the one that got away.