A former national secondary schools water polo (and rugby) player, Afeaki spent his youth at Auckland's Sacred Heart College, developing a gigantic lung capacity with his anaerobic fitness.
Former All Blacks selector Peter Thorburn remembers his physical prowess from a national under-19 camp in Rotorua.
"He did a 400 metres in 56 seconds which left everyone gob-smacked."
To put that in context, top Kiwi track athlete Nick Willis averaged 56s per lap on his way to the national 1500m record of 3m 31.79s last year. Afeaki claims he's only ever done 58s.
Urban legend or not, he's got serious toe for a big man, much like prop Steve McDowall used to be the fastest All Black over 20m in the late 1980s.
"He's a brute of a guy," Thorburn says of Afeaki. "But he was never fat, he just had a big frame. At the other end of the spectrum, he could run 3km in 11 minutes. That's a standard measure for rugby aerobic capacity. By comparison, Jonah [Lomu] never broke 18 minutes for that distance. That's not to denigrate Jonah. He made up for it by sheer force of nature."
Living in North Harbour, Afeaki entered Super Rugby as part of the Blues wider training squad in 2010 but moved to the Chiefs last year because of the difficulty getting past Tevita Mailau, Charlie Faumuina and John Afoa into the first XV. It has proven a masterstroke, as the Blues season tails into oblivion.
Afeaki is in contract negotiations to re-sign with the Chiefs. His current deal ends this year. Former All Black prop Craig Dowd observed Afeaki as part of the North Harbour rugby academy. He says he is an All Black in the making.
"He was unlucky not to be picked in that initial [2012] squad through injury. His [20-year-old] team-mate Ben Tameifuna got picked but Ben [Afeaki] is two to three years ahead of him in propping development. [Tameifuna] is also a good prospect but I don't believe he's a test rugby contender just yet.
"We need a genuine back-up to Owen Franks at tighthead. Ben Afeaki is the man for me at the moment. He must be close but there's not much you can do about a broken arm. They couldn't pick a guy who hadn't played any rugby.
"Ben has a huge work rate for a big man. All those years in the pool have given him quite a motor. He carries well, has a ton of pace, good defence and, at 1.93m, is a strong lineout lifter. He also scrums well with that barrelled torso."
Thorburn says Dowd helped Afeaki improve his scrummaging: "He perfected his technique because it is difficult for young guys to match wilier opposition who bore in, drag you down or get underneath you. It takes several years to learn your trade."
Thorburn also reserves praise for the work Chiefs forwards coach Tom Coventry has done with Afeaki as part of moulding a mobile, skilful pack.
Afeaki agrees Coventry has helped them gel.
"He brought in more pick-and-go, plus we do a lot of mauling during the week. We also want to get rid of the Chiefs' reputation for going missing at scrum time."
Orthopaedic surgeon Dr Chris O'Meeghan gets a plaudit too, for bringing Afeaki back into All Black contention before the end of the Super Rugby season.
"I spent about four weeks away from the Chiefs group but came back and fitted in. Chris didn't try to force it and neither did my physio. He put titanium plates in my arm and I did no contact work until the last week of my rebuilding. The plates will stay there for a while. I don't think they pose a great risk to airport security," Afeaki laughs.
"I actually lost a couple of kilos coming back to rugby. I did so much cardio work and ate healthy in the interim."
