Still panting after just completing the race, Dixon told the Herald he "maybe" could've managed a fourth lap.
"It was just fabulous, demanding, I was red-lining. Back in my day i could run a marathon, but that was tough."
He said battling it out with other riders motivated him to pick up the pace.
"It was like a piano accordion . . . they got away on me up the hill and then I hammered it on the way down to catch up. It was absolutely magnificent."
Meeting up with other athletics legends was a highlight of the event, Dixon said.
"It was fabulous spending time with Sir Peter Snell and Sir John Walker on opening night, celebrating our friendship.
"This is what it's about. [For] 44 years, [John's] been my mate and that means a lot on the journey. There's no destination, it's just a journey.
Roe had originally planned compete in rowing, but an injury sustained during training forced her on to the bike.
She said there were some similarities between running a marathon and mountain biking.
"It's kind of a leg sport, when you're running you're obviously using your legs and your arms but you get a seat and get to sit down, which is quite nice.
"There's a whole competitive aspect but the irony is that I've never raced on a mountain bike before.
"I'll be relying on my fitness and my agility, and it's a bit of a who knows what's going to happen really."
She said the World Masters Games event was "all about the love of sport".
"I got into sport because I love it, and I think the older we get the more important it is to be involved in sport because otherwise you get stiff and old, and you don't want that."
Roe said she didn't have "any gauge" on how she might perform, but was "hoping to get there in good shape".
"I've had a good six-week run up but that's it, I'm feeling good about it."
