How Emma Stone Gained 15 Pounds for Battle of the Sexes

How did Emma Stone transform into tennis legend Billie Jean King?
It took a lot of sled pushes, protein shakes and a man named Jason Walsh.

Jason is a celebrity trainer and founder of Rise Nation fitness center. He worked with the La La Land lead to put on major muscles for her latest role in the new film Battle of the Sexes.
"Emma took it very seriously," he said. "This is somebody's story that she's taken on. She wanted to make sure she could do everything possible to portray Billie Jean King in the right way."
The first step: nutrition. Jason said they needed to dial in Emma's diet by increasing calorie and fat intake, which helped for her to put on weight. Emma isn't built like a tennis player or a pro athlete, so in order to look like one, putting on those pounds and muscle was essential for the aesthetic element of becoming Billie Jean. According to the celeb trainer, the easiest way to accumulate those calories is to drink them.

Jason used a protein called Metabolic Drive as a base (apparently, this is actually kind of delicious) with a handful of spinach for fiber and micronutrients plus some Ashwagandha, a powder used to ease stress on the body. He would also add a few tablespoons of Udos oil as a pure source of high-octane, clean fat.
"The last thing you want to do is force someone to eat a lot more food. Your hunger is going to go up naturally because your metabolism is going to go up from the training," Jason explained, adding that Emma became almost insatiable because of the intense workouts he was putting her through. "Protein shakes were an easy way for us to get a lot of nutrients and a few hundred calories in a single drink that tasted really good. She actually looked forward to it."
As for training, Emma would meet Jason five days a week, twice daily for four of those five days. Eventually, Jason transitioned the actress into fewer sessions as filming approached. In the mornings, they would work on what James calls "complex movements": sled pushes, squats and lunges—the heavy stuff. The afternoons were for "secondary movements," or what Jason describes as "less taxing, but good for aesthetics." Think exercises that target the abs and arms.
For conditioning, Emma would go to Rise Nation once or twice a week, which consists of 30-minute, high-intensity climbing classes for cardio.

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Is anyone else getting tired just reading this fitness itinerary?
"She's very lean as is so we didn't have to focus on getting her body fat down," Jason said. "She put on 15 pounds, and that was really the goal from the beginning: to put on that kind of weight, to give her the confidence and to keep her healthy. And she nailed it."
According to Jason, Emma was doing 300-pound hip thrusts, a few hundred pounds on sled pushes and her dead lift was up to around 185 pounds (wow!). But Jason is most impressed with is the star's resilience.
"What I'm really proud of for Emma and for actresses like her that we end up training is that we keep them from getting injured," he said. "When an actor has to play tennis all day long and do all these things for a movie, the chances of them getting injured if their body isn't strong and resilient is pretty high. Then that's going to stop production, and you've got other issues there."
He also said that with Emma's training came with powerful psychological benefits.

"It gave her a level of confidence and it helped her believe that she was [Billie Jean King]. It really does give women confidence to be strong like that."