The next actor to play Superman, David Corenswet, put on 40 pounds to play one of Hollywood’s most iconic roles, his personal trainer told Business Insider.
Paolo Mascitti said the goal when preparing Corenswet for “Superman: Legacy,” which is out in July, was to build muscle mass and size rather than get super-shredded.
He needed to look “more like a farm boy than a complete bodybuilder,” he added, which involved eating up to 4,500 calories per day of whole foods with the occasional treat.
To achieve this look, they trained five to six days a week starting in July 2023. Although it was challenging to stick to their training schedule once filming was underway in March 2024, they did what they could.
“He had a very, very good attitude and he worked really hard,” Mascitti said. Corenswet was also very relaxed, Mascitti added: “He listens to jazz when he works out.”
Mascitti shared the workout and nutrition plan he used to get Corenswet Superman-ready.
Paolo Mascitti
Corenswet did compound exercises that got progressively harder
Corenswet followed a push-pull-legs split: meaning they focused on “push” exercises, such as bench presses, one day, and “pull” exercises, such as pull-ups, the next. On day three, they’d do leg exercises like squats, then restart the cycle.
They trained with progressive overload — gradually increasing the weights and reps to keep challenging Corenswet’s body— and focused on compound movements (multi-joint exercises, like shoulder presses) plus some isolation exercises (such as bicep curls).
The rep range varied but usually was between six and 12, occasionally going up to 15 or 20 reps on isolation exercises, such as cable flies, to fatigue the muscles at the end of each workout, Mascitti said.
While the goal was mostly to gain size, Corenswet needed to be strong and fit for the physically demanding role. They also did a lot of core work to support Corenswet when he did stunts and harness work.
Corenswet ate 4,500 calories of mostly whole foods daily
Corenswet gradually built up to eating 4,500 calories per day to build muscle without putting on too much fat. He dropped to a slight calorie deficit of around 3,500 calories a day as filming approached, to shed some body fat.
Corenswet mostly ate whole foods as the quality of calories was as much a priority as the quantity.
His high-protein diet was split like this: 50% carbs, 30% protein, and 20% fat, Mascitti said.
He aimed to eat 0.75 grams to one gram of protein per pound of body weight daily. This mostly came from eggs, dairy, chicken, red meat, fish, and whey protein spread out over the day.
His carb sources were mostly rice, oats, sweet potatoes, and vegetables. The diet wasn’t too restrictive, though, and Corenswet also ate French toast and waffles from time to time.
“He loves cereal, that’s his kryptonite,” Mascitti said.
Corenswet mostly ate higher-carb meals before workouts for energy.
The fat sources were mostly olive oil, avocado, and seeds.
An average breakfast, for example, was six egg whites, two whole eggs, 1.5 to two cups of oatmeal, some berries, Greek yogurt with almonds, and a protein shake.
The rest of his meals (he ate seven times a day) might have consisted of rice and a protein source like beef, chicken, turkey, or fish, along with vegetables such as broccoli, and a protein shake.
Corenswet snacked on protein shakes or unsweetened Greek yogurt with berries.
Sleeping enough was also important to complement the training and nutrition.
“Everything is part of the puzzle. You take one of the things out and it’s not going to happen,” Mascitti said.