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Tanerau Dylan Latimer's rapidly filling-out 98kg frame contains a unique blend of fibres.
There are the fast-twitch fibres, which create his explosiveness. He hits opposition rugby players hard and has considerable acceleration, which can send him shuffling through the smallest gap and away into space.
There are the slow-twitch fibres, which ooze oxygen and maintain his incredible stamina through 80 gut-wrenching, lung-burning minutes of frantic activity which the openside flank position demands.
Fusing all these sinews together, however, is a fibre that has made him who he is - a 19-year-old Te Puke boy at heart, a giant-sized role model with a champion attitude in reality.
His moral fibre.
His Rangiuru club coach Bob Moorehead describes Latimer as a man of content. In Moorehead's world, there is no greater compliment.
Latimer trains hard, he lives cleanly, he adores his girlfriend Alana Clover, he respects his elders, he smiles and laughs politely and he holds his head high.
Above all, he loves his mum Meretupou Skudder. He's proud of her - she's just finished a health care assistant certificate at polytechnic and has started a new job - and she's equally proud of her boy, who is off tomorrow to join the Crusaders for their Super 14 campaign.
Latimer admits he grew up 'on the wrong side of the tracks' in Te Puke. It's not a place for aspiring young sportspeople wanting to forge professional careers. Teenage crime is high. Drugs are rife, and gang activity hangs like a haunting shadow.
But Meretupou Skudder wanted more for her son, who can count former All Black George Skudder and recent New Zealand Maori coach Matt Te Pou as uncles.
As soon as he could float, she enrolled him in swimming classes. She wanted him to be safe in the rivers and beaches that her family frequented, and also wanted to instil a sense of discipline in the young boy.
"I never liked swimming!" Latimer laughs, admitting he was pleased to give it away four years ago to concentrate on his rugby.
"Mum made me do it, just to keep me away from the streets in Te Puke and away from my cousins, so I wasn't led astray. It worked, definitely, and I'm grateful and I thank her for that. Back then I wondered what I was doing it for but I realise now it was for my own good."
Latimer's athletic prowess meant he was soon a successful national age-group swimmer and eventually he came under the guidance of master coach Clive Power.
But that meant mother and son had to rise at 5am to make the journey from Te Puke to Greerton, to get there in time for training. For afternoon sessions, Latimer's mum enlisted her own mother Martha Skudder and niece Ringa Moana.
It was a sacrifice she was more than willing to make.
"Like all boys say, he told me he wanted to be an All Black," Ms Skudder said. "I'd often bring it up when he didn't want to go to swim training. I told him we'd only get there if he kept on working and I kept on working with him.
"He found it hard at times. There were a few times there when I just had to have no ears and not listen to what he was saying. It was a hard time for me but we got through it and he did well."
"I've always said to him if he could get through Clive Power's training, he could get through anything!"
T anerau Latimer's rugby talents were recognised at a young age, but his work ethic, fostered by his swimming, was what stood him apart.
Bay of Plenty academy manager Dean Jennings has watched his young charge - who graduated from the academy with honours upon his Super 14 selection - rise through a superb schoolboy career.
"Tanerau's the hardest trainer I've ever seen," Jennings said. "His fitness levels are superb and he's a gutsy player on the field. But he's also always so keen to learn and that's his biggest asset. He's a great example to other young rugby players."
But Latimer admits he didn't always listen. It was only when national sevens coach Gordon Tietjens plucked him out of school and put him on the world stage that he really began to appreciate advice.
"I didn't have my ears open a lot back then - I didn't listen much until I made the sevens side. Coming into the professional era, you've got to listen. It's your job to listen, and if you don't, the boys get angry and the coach gets angry. Sevens has changed my life."
This week while Tietjens whittled down a group of 25 players to his 12-man IRB world series squad in Mount Maunganui, Latimer was sideline running water bottles.
He certainly didn't have to, but the young man was eager not to lose contact with his friends in the side and with the game which has helped make him.
He has set his sights firmly on making the Commonwealth Games sevens squad and joked he was at training keeping an eye on Matua Parkinson to make sure he didn't get the jump on him.
Of course, Super 14 is now his priority. He'll head south as an apprentice to All Black openside Richie McCaw, to work again with Steamers coach Vern Cotter.
Cotter's brief for the young flanker during the NPC season was to watch and learn, and pick the brains of Parkinson and fellow loosie Nili Latu, which he did.
"I didn't even know about certain lines to run. I've always just run to the next breakdown, but they taught me a lot about the lines to run to get there and the ways to get there to be more effective. Though I don't think Nili wanted to give too much away - because I'm a Crusader and he's a Chief!"
The gym has also been his second home. His body, nearly fully matured, has gone from around 90kg at the end of the last sevens season, to close to 100kg, valuable extra padding for withstanding the knocks of professional rugby.
Latimer knows he has struck the winning lottery ticket with a Crusaders contract. If a player can't use their set-up to vault into the All Blacks, chances are he will never make it.
But Bob Moorehead's theory on 'content' is strong on loyalty.
So is Tanerau Latimer. Bay of Plenty will be his NPC province for the forseeable future, and Te Puke will remain his home town. He'll keep demonstrating the power of strong parenting and a stout heart.
He owes his mum that much.