"I turned to my mate and said we can do it quicker next time so the next time we did it we turned to each other and said over a cold beer we can do it in quicker time so we just got hooked by that," says the 46-year-old beer/wine packaging equipment company owner.
"It's always over a quick beer. It's also over approaching middle age and a bit of male ego or whatever."
O'Keeffe routinely takes three months of regimented training to lead into any event of that intensity.
For the Triple Peaks it entails becoming familiar with the peaks with a couple of friends three times a week, including weekends, over varying distances.
"I run with a guy who won it a little while ago and ... he's over 50 now so he's really old. He's on the dark side of 50, shall we say," he says of Ross McIntyre who still runs but he suspects is looking for something to inspire him.
Ironically it took a meaningful entry for O'Keeffe to make it a part of his life.
He did his maiden solo run in 2009 when he ran alongside friend Chris Mellors in memory of the latter's daughter, Georgina, who died of a brain tumour in May 2008 when she was only 14.
That spawned a trust, with the help of another friend, Jesse Williams, as a tribute to the community's generosity for its charities and anonymous donations through difficult times and to reciprocate to others who are in a similar predicament as well as ensuring Mellors' daughter's name would not be lost.
O'Keeffe's children are all sporty but they don't do Triple Peaks-type of events.
Havelock North High School pupils Ellie, 16, and Hannah, 14, play netball and flirt with orienteering while Callum, 11, of Lindisfarne College, plays hockey and and is a budding triathlete.
"He's a bit of a runner so he wants to do the Triple Peaks at one stage and an Ironman," says the father.
In that respect, O'Keeffe considers his involvement today a personal one to keep fit and defy age.
Conversely he sees how that is rubbing off on his children where the inspiration can even be something as simple as the desire to beat their dad.
"It gives us something to do together so it becomes a bit of a bonding thing, especially for my youngest boy if we want to go for a run, a bike ride or just a run up the peak so it's cool to be just out and about."
Wife Lucie also is sporty but O'Keeffe salutes her for her undying devotion to chauffeuring the children around to their activities, including Hannah's equine sport interests.
"It's easier for me to sneak out in the mornings because my preparation time is relatively modest so Lucie's been a fantastic support for me when I've done these type of events," he says of his English-born wife who did a leg of the Triple Peaks a couple of times as part of a relay team.
O'Keeffe recalls some melancholic reaction to when the challenge in 2014 but he actually enjoyed having to come through the village three times.
"You felt, although you were doing like an offroad or adventure race, that you were right in the middle of the village.
"I enjoyed it for what it was and it was quite a cool way to do it so it's hardly a kilometre longer than the other one, supposedly."
He recalls when he was at the peak of Mt Kahuranaki psychologically it made him feel like the race was a little drawn out through isolation.
"This one can potentially feel hard but you'll be close enough to be part of the village," says O'Keeffe.
That's a problem teenager Flo Mills won't have even though she is an under-19 solo runner today for the first time.
Mills and five other fellow HNHS - Jenna Tidswell, Kaiyin Hardy, Thomas Culhan, Oscar Smyth and Hamish Jackson - also will be running together but not officially as a team.
"We're doing it to stick together and have fun together," says the year 13 pupil of all the solo first-timers who have competed as a team in the previous two years.
They are using today's run as training for the annual Hillary Challenge Adventure Racing secondary schools' finals at the Tongariro Outdoor Events Centre in May after the pupils qualified last year.
Mills' inspiration comes from her parents, Te Mata School teacher Diana and builder Roy Mills, who also will compete as solo runners today.
"We've always been going up to the peaks from the time we were little," said the 17-year-old who is a sports captain at HNHS with O'Keeffe's daughter, Ellie, as her deputy.