Jordan Kahu pulls off an acrobatic finish to score for Brisbane against the Sharks in Round 9.

Most players in the NRL have a number that they consider to be their optimal playing weight but Broncos utility Jordan Kahu has revealed that he fluctuates his weight depending on which position he is playing that particular week.

One of the most versatile players in the competition, Kahu will line up on the wing for Brisbane against the Sea Eagles on Saturday night but has played NRL and Test football in the centres and at fullback.

In an age where outside backs rarely come in under the 100-kilogram mark, Kahu bravely puts his 92-kilogram frame on the line week after week and while happy with his playing weight, admitted that he does make subtle adjustments.

And his key to either putting on an extra kilo or two or shaving it off? Bread.

"Anyone will know this; you eat a lot of bread but you don't really realise," Kahu told NRL.com.

"I have bread every breakfast so that's probably a tough thing, going from bread to cereal.

"It all comes back to what position I'm playing," added Kahu, who has played two NRL games in the centres this year and seven on the wing.

"When I'm playing in the centres I like to play a bit heavier than normal. On the wing I probably weigh in at 92 or 93 kilos but if I'm at fullback I prefer to play a bit lighter, either 92 or 91.

"If I know I'm playing fullback early I'll try to eat a bit less during the week. That's what I did last week for the Kiwis game.

"Early on in the week I don't have any breads and try and stay away from potatoes and pasta and all that kind of stuff. Just load up on those the night before a game."

Kahu's transformation has not been confined to the physical with the 25-year-old crediting the arrival of his daughter Jayla with the best football of his young career.

Since his partner Jess gave birth to Jayla eight months ago Kahu has played a key role in Brisbane's charge to the 2015 Telstra Premiership Grand Final, played for the World All Stars and represented New Zealand in four Test matches.

It's a far cry from the knee injuries that threatened to derail the career of the former schoolboy sensation before it even began and has helped to bring balance to his life.

"Ever since we've known she was coming last year it was my best year playing wise and I ended up representing New Zealand," said Kahu, who will play his 45th NRL game on Saturday night.

"Who knows if there's a coincidence or what-not but she has made me a really happy person and I think that has been showing on the footy field.

"After the games without Jayla there I used to dwell on things a fair bit. I'm really hard on myself as a player and if I make mistakes I don't really forgive myself until the next game but with her there I get home and all football is just out the window.

"I don't have to focus on anything at all, but just her. She always puts a smile on my face and she's made the balance in my life a lot better in regards to footy life and my social life.

"It's gone pretty quickly. I think I'm going to really miss this phase when she's a bit older and not as happy to see me every day."