Davies had similar motivations.
"Because I've always wanted to do a decent length triathlon and always wanted to learn to ride a mountain bike so this made me commit to that. And living in Rotorua, you have these things on your doorstep and you get to truly appreciate what Rotorua has to offer by training for these events."
If getting proficient on a mountain bike was Davies' goal, facing the swim has been the big challenge for Buchanan.
"I haven't done as much (swim) training as I should have, but I've been practising in the Blue Lake with friends who swim. It will be mind over matter on the day to just get through it.
"Mountain biking has been harder than I thought it would be but the training itself has been really enjoyable. I've been regularly swimming in the Blue Lake, which is pretty cool. It is hard trying to train six days a week around everything else, but you just fit it in. Luckily we have got very supportive husbands that's let us do that," said Davies.
Working to a programme and tacking a couple of smaller triathlons have helped.
"We did the Marra (sprint) triathlon at the Mount. It was a cool day and the kids did it too, and that's one of the reasons (for doing it) really - to inspire the children and get them to see their mum do it," said Buchanan.
Davies has an extra special reason for wanting to finish in one piece.
"I'd like to finish without an injury. I snapped my achilles just under two years ago and all I want to do is survive the event without an injury - I'm having my 40th birthday party that night so I want to be able to rock up to that in once piece."