Here's how Alicia Vikander gained 12 pounds (of muscle) for 'Tomb Raider'

Carly Mallenbaum | USA TODAY

Show Caption Hide Caption The new 'Tomb Raider' movie is an action-packed reboot Lara Croft, the independent daughter (played by Alicia Vikander) of a missing adventurer, must push herself beyond her limits when she finds herself on the island where her father disappeared.

LOS ANGELES — I wonder how many times Alicia Vikander thought to herself, while training for Tomb Raider: “Can my body handle this?”

The question must have come up while she was transforming into action heroine Lara Croft for the reboot (in theaters March 16) of the 2001 film starring Angelina Jolie.

Sure, the actress was under the careful watch of health and wellness trainer Magnus Lygdback (who'll next train Gal Gadot for Wonder Woman 2) for seven months prior to filming. And, yes, she had been a trained ballet dancer years before taking on the role.

Still, when I tried out Vikander’s punishing Lara Croft workout, there were a few moments where I felt my body pushing to that limit right before seeing stars.

Fortunately, I did survive one day of the exercises that turned Vikander, 29, the svelte star in movies including Ex Machina, The Man from U.N.C.L.E. and The Danish Girl, into the muscular rock-climbing, butt-kicking Croft.

Here’s what Vikander went through to reshape her body.

She gained 12 pounds of muscle.

Though my experience didn’t involve weight lifting, Lygdback says Vikander’s early days of prep involved plenty of strength training, a lot of food, and minimal cardio in order to bulk up her 5-foot-5 frame.

At first, the weight gain was jarring for Vikander, who’s always been lean, but Lygdback assured the actress that she’d achieve the right action-hero look. If you've seen the latest trailer for the movie, starring Vikander and her toned arms and back, then you know that Lygdback made good on his promise.

MMA fighting was part of the training.

Though Lygdback says he’s proud of all of Vikander’s Tomb Raider prep, he’s probably most excited about “the whole MMA fight,” he says. “You can tell that she looks the part."

To prep for fight scenes, Vikander learned to kick and punch like mixed martial arts athletes. I, too, got a taste of that training by striking a thick pad with the heels of my palms and the top of my foot.

They don’t tell you that this practice will immediately channel all of your aggression and drain every ounce of your energy. They also don’t tell you that holding the pad while someone else hits it, well, that makes your head throb.

But that wasn't where my workout ended: A variety of squats, bear crawls, push-ups, assisted chin-ups and medicine ball tosses followed.

Vikander did those exercises for an hour a day for six or seven days a week leading up to filming, in addition to training in rock climbing, swimming and more intensive MMA skills like chokeholds. While filming, she'd train every morning before makeup, which sometimes meant 4 a.m. gym visits.

"She's super-tough and hard-working," says Lygdback.

'Tomb Raider' reborn with Alicia Vikander Alicia Vikander takes on the role of Lara Croft, originally brought to the big screen by Angelina Jolie.

Vikander debuted her new form at the Academy Awards.

At the 2017 ceremony, a year after Vikander won her supporting actress Oscar, she returned with a freshly toned figure. And she didn't hide it. On the contrary: The black dress she wore to the ceremony and the green gown she donned at the Vanity Fair after-party displayed Vikander's muscular back.

“That was the first time the world got to see her and her transformation. And that kind of blew up the Internet,”says Lygdback. "That was a huge thing.”

By then, she was eating five times a day.

Yes, it is possible to get into action-hero shape without limiting yourself to skinless chicken breast and greens. (“Hell, no!” says Lygdback. “Enjoy life.”) Vikander’s diet — some of which I sampled — had much more variety.

For breakfast? Three poached eggs. Lunch consisted of a fish or other protein, slow carbs like potatoes or quinoa, and vegetables. Dinner followed the same rules as lunch. Between meals, there were "fistful-size" protein-rich snacks.

Those snack options included artichoke hummus (yum) and quinoa tabbouleh with feta, mint and lemon (delish).

“For me, it’s important that if you know what you’re doing, you can actually have good food and enjoy it,” Lygdback says. “And you’ll have a six-pack after eating it.”

But Vikander did even better.

The actress developed an eight-pack.

“You don’t see that too much in the movie, but she’s got an eight-pack” of abdominal muscles, says Lygdback. “I’m really proud about her core.”

Though not visible onscreen, Vikander’s strong core was crucial for preventing serious injury while she was getting beaten up onscreen. It helped her handle a variety of extreme stunts, including swimming in ice-cold water and getting thrown around on a raft.

But sometimes, she needed a rest day.

Vikander, a serious actor and athlete, isn’t someone who has trouble working hard. Instead, “she needs someone like me (to say), 'It’s OK. We’re going to take a step back. Take a day off. Relax,' " he says.

On the other hand, Lygdback can also motivate someone to keep going. In my experience, mid chin-up, one genuine cheer of "You're doing awesome!" from the bearded trainer is enough to inspire me to churn out two more sets, even when I feel as if I'm on the brink of passing out.

Apparently, my body could handle it. For a day.

As for months of this routine? Well, I'll leave that to Vikander.