He is best known for his intense roles in Hong Kong action thrillers.
But it's formerly wiry Nick Cheung's newly attained six-pack abs and taut hot bod that steal the limelight in his latest movie Unbeatable.
The respected Hong Kong actor plays an ex-convict and former boxing champion in the Dante Lam-directed mixed martial arts film alongside Taiwanese heartthrob Eddie Peng, who stars as his boxing disciple.
In the movie, which opens here on Aug 15, both actors show off their brilliant acting chops - and buff muscular builds.
However, 45-year-old Cheung said that preparation for his role was not easy and he went through gruelling training to attain his hard-earned chiselled physique.
Speaking to The New Paper over the phone from Hong Kong, the chatty and friendly Cheung said in Mandarin: "For nine months, I had egg whites for breakfast, chicken and eggs for lunch, and steamed fish or boiled chicken and salad for dinner. There was no sugar, no oil, no salt and no carbs."
He added: "It was such a tough period and it was mind over matter after a while. I depended on sheer determination and perseverance to get myself through that period."
There were times when Cheung could not even put the food into his mouth as it was too "bland".
Blend & puree
"I had to blend and puree my chicken breasts and drink it as I could not chew it at all," he said.
"Sometimes, I would drink non-flavoured soya bean milk to increase my protein intake when I could no longer take more eggs or chicken."
Eating all those egg whites even caused his urine to have a layer of foam that was an inch thick and he had to flush several times to get it all down.
But that wasn't all.
Cheung had to undergo tough boxing lessons and intensive gym sessions for up to four hours a day to portray his role convincingly.
Towards the last phase of his training session, he had to dehydrate himself to make the muscle lines on his body appear more defined - to the point where he wouldn't have to use the restroom for a whole day. As such, he reportedly suffered side effects like coffee-coloured urine and pimples.
But it all paid off.
The erstwhile low-profile star stripped for the cover of Jet magazine's June issue, which led to a significant boost in sales and social media attention.
On his hunky makeover, the father of one said his Hong Kong actress-wife Esther Kwan, 49, did not have too big of a reaction. He laughed and said: "My wife sees me every day, so her reaction is not as big as yours! She doesn't really care about me, all she said was that training must have been very tough for me."
Filming Unbeatable itself was strenuous for the versatile actor, as he broke his little finger during one of the fight scenes.
Cheung, who revealed that he underwent surgery a month ago, said: "I wasn't careful enough and one of the actors kicked me and I ended up breaking my finger. I had to take painkillers and continue filming."
He added: "Even though I've done surgery and had six stitches, the doctor said that my little finger will not return to its original form. In the future, I will look at my broken finger and reminisce about the good memories I had while filming this movie. It'll be a souvenir that the movie has given me."
Cheung, who has acted in the critically acclaimed Beast Stalker (2008) , The Stool Pigeon (2010) and Nightfall (2012) , said he would be extra careful when choosing roles in the future.
"I will still act in action films as I like them a lot, but I am not going to force it if I cannot carry out some of the difficult stunts myself. I will let the stuntman handle it instead. I still need to take care of my little finger."
Cheung's stellar performance in Unbeatable has won him the coveted Best Actor award at the recent Shanghai International Film Festival.
He had previously bagged multiple Best Actor trophies, including the prestigious Golden Horse Film Award for Best Actor for his role in the Dante Lam-directed Beast Stalker.
As for beating his Unbeatable co-star Peng, 31, to the prize in Shanghai, Cheung said matter-of-factly:
"I am excited to have won this. It is not every day that I get to win such a big award."
He added: "As for Eddie, he is still young and he has lots of potential. I am sure in the future, he will get his chance to win as well."
Nice hunks of change
Taiwanese actor Eddie Peng, 31, started out playing heart-throbs in Taiwanese idol dramas, sporting long fluffy hair which went well with his boyish good looks.
These days, he takes on more serious roles that show off his acting - and increasingly hot bod.
In Close To You (2010), Peng went through tough physical training to portray a boxer.
The following year, he showed off his muscular body in Jump! Ashin as a physically disabled boy who goes on to become a talented gymnast.
In Unbeatable, he plays a boxer - again - with a broad muscular chest, six-pack abs and not more than 3 per cent body fat.
Peng told the Hong Kong media: "Every day we train so hard to look like how we were in the movie. Even my mum couldn't recognise me when she saw the movie poster."
After ditching his cute curls last year, the baby of US boy band Jonas Brothers convinced us he's completed the boy-to-man transformation with a half-naked, armpit-exposing selfie - complete with abs, impressive "V line" and manly facial scruff - uploaded onto Instagram last week.
The snap caused a collective swoon from women all over the world who had to take a second look at how the former teen idol has, er, grown.
Justin Bieber who?
The 20-year-old US singer told US radio DJ Ryan Seacrest that it had taken him a day of "debating" with his elder brothers before he posted the picture. His intentions, he said, were pure.
"There are a lot of people running around without their shirts (off) these days so I didn't want to just add to the noise, but I felt like as a diabetic it's twice as hard to stay in shape... I just wanted to be an inspiration to those people," he told Seacrest.
"It's been a pretty hilarious reaction."
As he puts it himself, the 34-yearold US actor - best known for playing a chubby, lazy and spoilt rocker on TV comedy series Parks And Recreation - has been "fat for about the last eight years".
Part of that has been career-motivated.
He lost weight for 2011 sports flick Moneyball and 2012 political thriller Zero Dark Thirty and put on 27kg for the upcoming Vince Vaughn comedy Delivery Man.
Then in early July, Pratt posted an Instagram photo showing off a mean, six-pack-sporting fighting machine.
It was captioned "Six months no beer", but it's a little more complicated than that - Pratt's been on an intensive training programme to get in shape for upcoming Marvel superhero flick Guardians Of The Galaxy.
He told Screen Rant: "You really could do it in six months and all you have to do is book a Marvel movie and have a deadline. And if you don't and get fat, then you might get fired then it's easy."
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