James McAvoy‘s goal for his physique was clear – he wanted to look like a Greek God. While reprising the role of Kevin Wendell Crumb in the 2019 film Glass, the sequel to Split, McAvoy was required to spend most of his time as The Beast, the most dangerous of Crumb’s 24 personalities.

A superhuman cannibal with enhanced speed, strength and agility who was also capable of wall-crawling, McAvoy was tasked with embodying a physique befitting The Beast.

‘Unlike Split, I was The Beast most of the movie, and I was just outside in broad daylight as well, so I didn’t have too much cool studio lighting,’ McAvoy said on the Armchair Expert podcast. ‘So I was like, I’m really going to need to do the real thing. I’m going to need to go for it.’

He asked director M. Night Shyamalan to provide him with a trainer. Shyamalan offered to set McAvoy up with someone from a local gym. McAvoy disagreed – he wanted an expert trainer who could dedicate their time solely to building the Scotsman into The Beast over the course of five months.

‘I’ve worked with those guys before and they’re great. But I’m going to need somebody that can make me look like a Greek fucking figure from mythology,’ McAvoy said.

That’s why he enlisted the help of trainer Magnus Lygdback, whose celebrity clientele also included Ben Affleck and Alexander Skarsgard. Together, they built a physique McAvoy was seriously proud of, implementing four key training principles.

Because of The Beast’s superhuman physical abilities, McAvoy needed to not just look good – he needed to move better than a professional athlete. So, during their time training together, Lygdback didn’t have McAvoy immediately jump into heavy weightlifting. Instead, they focused on getting his body primed to look both strong and athletic on camera.

‘The guy that worked me was amazing,’ McAvoy explained. ‘He regulated what I ate, and trained me just right. For the first four weeks, he rehabilitated me.

‘I could walk, but I couldn’t run, couldn’t cycle, couldn’t jog. So he did a lot of rehabilitation and functional movement, and then put the pounds on me really fast. I was addicted to it for about three years, and I was honestly the biggest I’ve ever been.’

No matter how hard or well you train, if your nutrition isn’t focused, your results will likely suffer. McAvoy ate every three hours, counting his macronutrients religiously while focusing primarily on high-protein meals.

‘He was lifting already. He was working out but I could tell by talking to him that his programming was not great. His nutrition was not great,’ Lygdback says. ‘When I work with someone I step into their life. It’s not just that hour in the gym every day, it’s when do you go to bed, what do you eat, are you eating the whole portion? All those kind of things.’

In fact, McAvoy had dialled in his nutrition so well that he started looking too good during the training block – producers complained to Lygdback that the actor had got too big and needed to lose a little bulk. That meant making small changes to achieve the physique they wanted.

‘We had to make some adjustments. I reduced salts which binds water so he would get a little less bloated and gave him a little less carbs. But not much because I didn’t want to lose our progress,’ the trainer says.

Mixing up the exercises, weights, reps and sets all proved key for McAvoy’s training. The actor wanted to have thick traps and look as scary as possible, but needed to remain injury-free as he built as much strength and muscle as he possibly could.

‘We did some compound movements but I throw in a lot of isolated movements. That’s how you get results fast,’ Lygdback says. ‘You can’t deadlift to failure, for example. But you can do lateral raises to stress the muscle to the max. I start with a big lift then move over to isolated exercises to get the most out of each muscle group. It also reduces the risk of injury while working out.’

Regardless of how McAvoy felt – whether he was fatigued, unmotivated or it was extremely early in the morning – he would show up every day and put in the work.

‘And you can tell; to look like that after three months is pretty nuts,’ Lygdback adds. ‘I always say that as a person he is a great man. You don’t hear anyone say a bad word about him. He’s a fanatic human being.’

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