Zac Efron doesn't want to ''ever'' be as ripped as he was in 'Baywatch' again.

The 32-year-old actor dropped to just five per cent body fat in 12 weeks thanks to a strict low-carb diet and working out five or six days a week, often twice a day for his role as Olympian Matt Brody, who trains to become a lifeguard in the 2017 action-comedy.

And he has now admitted it was ''stupid'' to have to put his body under so much pressure to buff up, and insisted it would take something ''worthwhile'' for him to ever agree to do it again.

Whilst taking part in 'Hot Ones' - the celebrity YouTube series where stars tuck into flaming hot spicy chicken wings whilst answering questions - he said: ''That was actually a really important time to do 'Baywatch'.

''I realised, when I was done with that movie, that I don't ever want to be in that good of shape again.''

He added: ''It was so hard. You're working with almost no wiggle room. ''You've got things like water under your skin that you're worrying about, making your six-pack into a four-pack, s*** like that.

''It's just stupid. It's just not real. I'm happy that it worked, I'm happy that it got me through it.

''I may do it again if it was something worthwhile, but we'll wait until it gets to that. Take care of your heart, take care of your brain, you're good.''

The 'High School Musical' star shared that how, during his training, he was eating ''only organic grass fed/free range protein and organic leafy greens''.

Despite not wanting to drastically change his physique again, Zac was extremely proud of how his 'Baywatch' body.

He said at the time: ''I'm probably the physically strongest I've ever felt.

''Not in terms of bench press or how much I can squat, but in how quickly I could get out of this room and destroy everything in my path.''