Twilight: New Moon pin-up Taylor Lautner was deliberately given shirts that made his muscles stand out, the film’s costume designer has revealed.

Tish Monaghan says the teen’s costumes all had extra-short sleeves to emphasise his bulging biceps. “Everything was geared towards making sure that his arm muscles really showed,” she told a US mag. There’s a scene where he’s working on a motorcycle and his muscles are really pulling against this plaid shirt he’s wearing. He looks very strong and very built, and we tried to do the same with his T-shirts.”

Lautner, 17, plays werewolf Jacob Black in the film, which, despite its huge popularity, has been mocked for constantly featuring scenes in which he takes his shirt off.

Required to bulk up for the role, in which he changes shape amazingly, he obliged by piling on 14kg. Monaghan, from Vancouver said she had to come up with clothes which would emphasise his extra size.

“There was no way, since it was the same actor, that we could show somebody that had grown like six inches,” she said. “So it was Chris Weitz’s [the New Moon director’s] genius idea to tailor his clothes, to make the sleeves a little bit shorter, a little bit tighter – make it look as if he’s grown out of his clothes in a couple of months and hadn’t had time to go get new ones.