We earn a commission for products purchased through some links in this article.

'I felt the strongest I've ever felt in my life.'

Natalie Portman does not do things by halves. In prep for her role as a ballerina in Black Swan she practised ballet for five-ten hours a day, and the same unwavering dedication was deployed for her role in new Marvel movie Thor: Love and Thunder.

As a petite five-foot-three female, being asked to ‘get as big as possible’ in order to embody the Mighty Thor – who Portman’s character astrophysicist Jane Foster transforms into – was no mean feat, but was Portman phased? We’ll let her PT, Naomi Pendergast, answer that.

‘I never needed to motivate her, she never complained and, even though having to bulk up was hard for her, she took it as an opportunity to learn new ways to move her body.’ Together, Pendergast and Portman trained for nine months ahead of filming, two hours a day, and if you’ve seen the film, you’ll know they met the brief, and Portman has also come away with some learnings for life.

A post shared by Natalie Portman (@natalieportman)

‘I felt the strongest I’ve ever felt, and the most physically balanced ever,’ she tells us. ‘Before, I was much weaker on my left side, but Naomi worked with me to strengthen those muscles.’ One specific exercise intro’d by Pendergast is also now a permanent fixture in Portman’s routine. ‘I’ve continued with the daily sit-to-stands because Naomi told me it helps with lifespan,’ Portman tells WH, adding that she has, however, started to reincorporate some cardio sessions as that’s what she enjoys.

‘[Thor training] involved a lot less cardio and a lot heavier weights than I’ve ever done,’ she tells us. ‘Because I’ve never tried to bulk up before.’ One thing she wasn’t so sad to see the back of? ‘I never want to see another protein shake in my life!’ Portman told us, explaining that she ‘had to eat as much protein as possible for the first time’.

Food, fitness and keeping her headspace in fine fettle all played a part in Portman’s pursuit to get bigger, but while you’re probably not planning on training or eating in such an extreme manner anytime soon (pls don’t), Pendergast’s programme offers some useful tips that go for everyone. Take note.

A post shared by RPXFitnesstraining (@rpxfitnesstraining)

Whether your goal is fat loss, muscle growth or otherwise, it’s essential that you’re familiar with the effects of different kinds of workouts and how they could help you. It’ll save you a lot of agg (and disappointment, if you’re expecting results) in the process, promise. Portman’s go-to is usually ‘Gyronotic training’, Pendergast says – a ‘form of training that enhances the movement of your joints, as well as running. These are very different to the heavy weight sessions we did for the movie.’

Why was lifting so important? ‘The initial brief for Natalie’s training was to get strong arms and abdominal definition, but her role also involved a lot of stunts which meant we needed a focus on keeping her joints agile and avoiding injury.

‘Natalie gave this new type of her training her all, even though it wasn’t her favourite.’

Mighty Thor is THAT girl 💥 Witness her in action and experience #ThorLoveAndThunder, only in theaters July 8. Get tickets now: https://t.co/qFEBBR1B1O pic.twitter.com/gNx3WPIU9g

We’re forever harping on about the importance of sustainable lifestyle changes over quick fixes, and Pendergast telling us that the pair started training nine months before filming began is proof that even when you’ve got a temporary change in mind, slow and steady is the way to go.

‘In the first five months, we built up foundations we needed to safely bulk her up for her role and make her body resilient. Then, four months before filming, we started to increase the intensity of her routine and address any imbalances she had that needed correcting, to avoid injury,’ she explains.

‘Weekly sessions during the first five months involved conditioning exercises like stretching, balance work, stability training and cardio. But every week would be slightly different from the previous, and we’d progress the body so that it learned to take more load safely and effectively.

‘The last four months involved the use of heavy weights and progressive overload to build her muscle definition and bulk for the role.’

Here’s an example breakdown of a week's worth of workouts for Portman.

#MightyThor Check out the brand-new character posters for Marvel Studios’ #ThorLoveAndThunder. Witness it only in theaters July 8! Get Tickets Now: https://t.co/qFEBBR1B1O pic.twitter.com/w04Cg7nfSw

Although Portman’s training was purely to fulfil her role in Thor, it was still important for Pendergast to include some elements of training that she enjoys in their programme. Case in point: running.

‘Natalie loves to run so at the end of her session we would head outside a couple of times a week for a scenic run, or we would jump on the treadmill and do some fun sprint work. And we would always finish with some stretch and release work which Natalie really enjoyed,’ Pendergast adds.

It helps when you’re your PT’s biggest fan, too. ‘Naomi is the most incredible person to spend time with,’ Portman tells us. ‘She's a genuinely good person and is so committed and curious with her job. She’s always spending her free time learning new things about what she does. She also spent so much energy on making sure I was balanced so that I would not get injured, for which I am eternally grateful.’

Between using a foam roller, a massage gun, doing yoga stretches or just catching up on some much-needed kip, there are plenty of ways to ramp up your recovery. Naturally, Portman’s is a lil’ bit more indulgent, but the takeaway still goes: find recovery tools that work for you, and mainline them when you need.

‘Natalie trained five days a week so we would structure her workouts Monday through to Friday, then on the weekends she would have complete rest from any training. Her rest days would involve infrared saunas and massages, to get her body ready for the week of training ahead.’

If your goal is to build muscle, you need to eat more. Fact. As mentioned, Natalie’s main focus was an increase on protein – the building block of muscle tissue and therefore essential for muscle growth – but a calorie surplus was the underlining mechanism. Here’s an example of an average day of food for Portman, as shared by Pendergast.

A post shared by Micah Rose (@freckledmoonhollow)

‘This amount of food was obviously way more than Natalie normally eats,’ Pendergast says. ‘But it was essential for her to maintain this throughout filming to keep the muscle she had developed.’

You can read more about how to build muscle with the help of food in our complete guide.

Portman = hero. See what we did there?