O'Hanlon, 28, called it a day on his decorated career after a silver medal performance at the Rio Games in September, but the seven-time world and five-time Olympic champion is back thanks to his old man Terry.

The star sprinter left the sport due to its tough financial restraints, before his dad provided a solution which would allow O'Hanlon to continue racing.

"I made the decision to retire after Rio because I wasn't enjoying it as much and I was getting worried that if I started a family I wouldn't be able to support them," O'Hanlon said.

"Then dad suggested I work for the family architecture business part-time which would allow me to train in the morning and work in the afternoon.

"I didn't really know that was an option but dad is an architect in Sydney and I've got a landscape architecture degree so it makes sense.

"It's going to be very different going from being one of the best in the world at what I do to working in an environment I'm very unfamiliar with."

O'Hanlon has competed in the T38 classification for people with cerebral palsy since leaving school in 2005 and has represented Australia at three Paralympics.

The experienced racer is preparing for the World ParaAthletics Championships in London in July where he hopes to wind back the clock and claim his first world title in four years.

"My personal best is 10.79 and Rio I was supposed to go even faster but I had cramps in the heats and ran 10.93 in the final, so I'd really like to come back and win in July," O'Hanlon said.

"It won't be easy with a reduced schedule and my coach Iryna Dvoskina is still in Canberra which means I'll be doing a lot of training by myself, but I'm definitely going to try and win."

O'Hanlon acknowledged the tough financial realities which most Olympians face was the most significant factor that led to his initial retirement.

But the speedster added there was more than one reason he left the track and emphasised a more balanced approach to the sport is vital moving forward.

"It was just the full-on lifestyle where you're always locked into a routine and you can't just go to the coast and relax with your wife because you've got to train," O'Hanlon said.

"When you're travelling half the year it's hard to have a proper life, I'll still do my best to run as fast as I can, but running isn't the be all and end all."

O'Hanlon is married to Czech Republic Olympic race walker Zuzana Schindlerova and the duo relocated to Sydney just in time for Christmas.

"Working part-time will give me something else to concentrate on, my whole life has been about running fast, but now I'm adjusting to hopefully having a family in the near future," O'Hanlon said.

"I'm working in the family business and they're all very good at what they do so it's going to be a steep learning curve.

"It's pretty similar to a big race - I'm nervous but excited at the the same time - I've just got to look at this race as a marathon and not a sprint."

O'Hanlon moved to Canberra in 2005 after gaining a scholarship to the Australian Institute of Sport and went on to win 100m and 200m Paralympic gold medals in Beijing 2008 and London 2012.