Sebastian Stan nearly was Captain America. He lost out to Chris Evans for the leading role in “Captain America: The First Avenger,” and instead played the role of his sidekick and best friend Bucky Barnes. Stan saw it as a blessing in disguise as Evans packed on about 20 pounds of muscle to play the lead role. Stan told Details.com, “I like to be lean and flexible. I’m not interested in gaining size.” To keep his six-foot, 165-pound frame lean and muscular, the Romanian-born American utilizes Aeroboxing, developed by celebrity trainer and former professional boxer Michael Olajide Jr. In addition to his role in “Captain America: The First Avenger,” he has been in “Gossip Girl,” “Black Swan,” “The Apparition,” “Hot Tub Time Machine,” and “Gone” among others. While he played the best friend of Captain America in the series’ first film, he was his enemy in the second installment, playing the role of Winter Soldier in “Captain America: The Winter Soldier.”

Aeroboxing

Michael Olajide Jr. once fought for the super middleweight title in 1990, but lost that bout to Thomas “Hitman” Hearns. He retired a year later after becoming blind in one eye. Fast forward over 20 years and he is a world-renowned celebrity trainer and owner of his own gym, Aerospace. His clients include Stan, Mark Wahlberg, Hugh Jackman and Adriana Lima. So what is aeroboxing that makes these celebrities coming back? Aeroboxing is a cardio and strength training regimen that combines boxing moves, jumping rope and strength training. At the end of each session, Stan said, “You end up in a pool of your own sweat. It’s hard to keep up with the boxing combinations unless you’re really focused, so it’s also a great mental workout.”

Workout

Stan performed this workout three to four times per week with at least a day of rest in between each session. These grueling sessions under Olajide’s guidance are an hour-long and are divided into three circuits with no rest in between.

Circuit 1 – Shadowboxing

Eight to 10 minutes of shadowboxing holding dumbbells ranging from five to 15 pounds

Circuit 2 – Cardio

Five minutes of jumping rope nonstop. At every eight count, perform a double under.

Circuit 3 – Strength Training

Eight to 12 minutes of resistance work with no rest in between. There are three specific moves including standing ab work, push-ups and squats. Standing ab work is performed with a 15-to-20 pound bar and encompasses a variety of moves. Push-up and squat variations are done for 30 seconds nonstop. Variations for push-ups include normal push-ups, push-ups with weights in each hand and tricep push-ups among others. Squat variations include normal squats as well as squat jumps and one-legged squats among others.

To fight Captain America, you need to put the training time in. Are you ready?