The 55-year-old from North Balwyn in Melbourne remembers the Eureka effort.
"The Eureka Climb is as much a mental challenge as a physical one," he said.
"I am not a particularly good runner so it took me about 16 minutes, which is not a long time to be pushing oneself for a distance runner.
"It is the thought of all those stairs that is scary, plus doing something new.
"It differs from some other skyscraper climbs that I have read about as in the Eureka Climb the runners are sent off in waves throughout the morning so there is no mad scramble to get to the stairwell first," Worsnop continued.
"Also walkers ascend a separate stairwell so there is no congestion during the climb.
"So it is a matter of each runner facing each of those 1642 steps him/herself and toughing it out to the top."
It became hard work.
"Initially one has to subdue one's excitement and not go too hard at the beginning so there is something left to finish off.
"The legs began to ache and the breathing became laboured, but I kept trying to convince myself that this is just like pushing hard in a 5km race - so get on with it.
"It got quite hot and stifling running in a stairwell as there was no fresh air feeling on the face - and the sweat was dripping and clinging, reluctant to evaporate in the still air.
"I found that my feet hurt the most as I got higher. As the steps were quite narrow, I could not put my heels down so I as running on my toes all the way and this put quite a strain on my foot muscles. But stop complaining and get on with it."
He made it. But Worsnop hasn't studied the guy/gal event too hard:
"I am not sure about the gnarly guy/girl. Does it have something to do with mud and hills? I don't know, but I thought I would give it a go and have some fun. I have not done events like Tough Mudder - although my son did it last year - as I see myself as a runner and too many obstacles would get in the way of running.
"I have done interesting runs though. Last week I did the Rip to River 10km which is all on sand along a beach near Melbourne.
"Last year I did a 'Bitumen is Boring' race in Plenty Gorge.
"There had been some heavy rain so the course was not only hilly, but very muddy.
"I had a fall and ended up winning the prize for the muddiest and bloodiest runner of the day.
"There is not much mud in Melbourne at the moment, just dust and snakes which I have to dodge occasionally as I train along the bike tracks.
"So I am not sure what to expect in Wanganui. No doubt there are hills? Mud? Snakes?"
Worsnop has been a club athlete in Melbourne since 1978 with Old Xaverians' Athletic Club he is now the president of this 'old boy' club from Xavier College.
He has done a few Masters Games in Australia, including the World Masters in Melbourne.
