Bernard Robinson (40) and Tracey Woodford (36) competed in the 100km race around the Blue Mountains, west of Sydney, last weekend and both said they would do it again.
"They tend to say your endurance gets better as you get older," Robinson said.
The Queenstown engineer crept over the finish line in 18th place in 11hr 50min and although he went through some physical and mental pain he was "keen to do a couple more".
Preparation for the race involved this year's Coast to Coast race, where he placed seventh, and the inaugural Godzone adventure race in April.
"You go through some pain and a lot goes through your head, because you have a lot of time to think, but the sense of achievement at the finish is worth it.""You're on your own out there and you're fighting your own demons."
With a 50km race and a 100km race under his belt, the "next step" may be the 125km Canadian Death Race in the Rockies this August.
"I'm over there for a 40th birthday, so if I change my flights, I could fit that in."
His Queenstown mate Morgan Garande (36) joined him in the race but was unable to finish because of an inflamed tendon.
Garande said he would give the race another go next year.
Asked if top-flight athletes were born great or achieved greatness, Robinson put his success down to being an outdoors type.
"I've always been into the outdoors.
" I think anyone can do anything if you put your mind to it."
Woodford, who was placed 27th in the women's category with a time of 15hr 13min, echoed that sentiment, vowing she would keep taking on ultra marathons "until nature takes its course".
"I heard it was quite a technical and challenging race and I wanted the challenge."
This was her "seventh or eighth" ultra marathon and, although she was only out to enjoy the race and "take it easy", her competitive streak took over and she pulled out all the stops.
"It was tough terrain. You had to have your wits about you.""You had people up your bottom, so you had to keep up the pace, for the first 20km especially.""The aim was just to enjoy it, but once you get caught up in it all ... when it comes to race day you get competitive."
Like Robinson, she has plans for more ultra marathons, but over the winter she plans to "ease up and maybe do a couple of marathons, but no ultras".
"It can get expensive, doing it all year round."
