The months leading up to Avengers: Infinity War, the costume department had some shiny new hardware for Sebastian Stan’s Winter Soldier. The character’s iconic bio-arm was getting an upgrade, which meant measuring Stan’s arms to create the piece. But when the actor reported for duty just a few months later, those readings were rendered null and void after Stan bulked up for the role with trainer Don Saladino.

The two have worked together since the antihero’s first appearance in Captain America: The Winter Soldier, and though the physicality has been impressive throughout the franchise, their path to it has been different every time. In this case, Stan was coming off of playing Tonya Harding’s ex-husband Jeff Gillooly in I, Tonya, which required a very different kind of body. But he and Saladino worked on building that muscle back up quickly.

“I think the way to succeed with your biceps and shoulders starts with how you are training the rest of the body,” says Saladino. “The fact is, it isn’t a major muscle group, so I like to throw in an arm day when the rest of the body isn’t feeling up to being pushed. When you are trying to build the arms, I always like to start with a heavy movement, putting pressure on the tissue.”

Saladino also says that the foundation for their success lies in a lot of carry and kettlebell work. “It all comes down to grip strength,” he says. “That is what is going to get you moving that right amount of weight.”

How to Get Arms Like the Winter Soldier

Don’s Superhero Kettlebell Carry Workout

The weight should be challenging, but not so much that it compromises form. Take as little rest as possible between the exercises. Complete this program once, but if you want to take it to the next level, go for a bonus round.

Overhead Carry: 50 yards (each arm)

Rack Carry: 50 yards (each arm)

Bottom-up Carry: 50 yards (each arm)

One-arm Suitcase Carry: 50 yards (each arm)

Farmer’s Walk: 100 yards

Don’s Superhero Arm Circuit

The weight should be challenging, but not so much that it compromises form.

Heavy Barbell Curl: 4 sets, 8 reps

Skullcrushers: 4 sets, 8 reps

Hammer Curls: 4 sets, 12 reps

Tricep Pushdown: 4 sets, 12 reps

Avengers: Infinity War hits theaters April 26, 2018.

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