• Jennifer Garner stars in the upcoming action-thriller "Peppermint," where she plays a vigilante mom who's out for revenge.
• To prepare for the role, Garner added boxing and martial arts to her routine.
• She also engaged in daily Cryotherapy sessions and uses the famous "Body By Simone"exercise method.
• Garner's Instagram reveals that she enjoys to grow her own food and cook meals herself, which allows for a more organic and healthy diet.

Jennifer Garner has been making headlines again, and this time it's not for doting on her kids or transforming into a viral meme. Rather, it's for transforming her body to prepare for the upcoming September thriller "Peppermint," in which she plays a vigilante mom who's bent on revenge.

"To do action for the sake of action has never interested me but this script was so smart,"Garner told People at CinemaCon. "This was to avenge your child's death, and there's no bigger reason to go out and get into really good shape and then kill people."

Indeed, Garner has been showing off an impressive new physique, which she said is the result of adding boxing and martial arts into her workout routine, according to People. She also shared a look at her intense workout sessions on Instagram, introducing the video as a "Recipe for Turning A Mom Back into Action Lady."

"Everyone gets very invested and are you going to actually look the way we want you to look," she said at CinemaCon, referring to her preparation for a physical, action-packed film. "I don't know if I did, but I just always followed what felt right to me."

Garner also revealed on Instagram that she has embraced daily Cryotherapy — a procedure that involves standing in a chamber of up to -130 degrees Fahrenheit for a couple of minutes — and often works out with her friend, celebrity trainer Simone De La Rue. 

De La Rue is known for her exercise method "Body By Simone," which is also celebrated by celebrities like Reese Witherspoon and Anne Hathaway. 

Garner's social media presence also gives fans some insight into her healthy eating habits. She recently posted recipes for both beet chips and kale chips as substitutes for her "nemesis," blue corn tortilla chips. Garner is apparently an avid cook,and has even attempted homemade bagels.

Another post revealed that Garner starting working with Kelly LeVeque, a self-described "holistic nutritionist" and "wellness expert," to get in shape for "Peppermint."

"[I] have had her smoothie every day for breakfast," Garner wrote in the caption. "Today, I decided to play scientist and see if my @onceuponafarm cold-pressed, organic purée (or baby food, if you're a baby, but whatever) could be a substitute for fresh blueberries when I didn't see any in the fridge. Yep, it could."

"Don't be scared! It's tastier than it looks!" she added.

LeVeque is favored in Hollywood for her meal formula, dubbed the "Fab Four." She encourages clients to combine protein, fat, fiber, and greens to "turn off hunger hormones, squelch inflammation, and provide the body with the perfect complete meal of essential nutrients," according to her interview with MyDomaine. 

Garner recently told People that she and her three kids have their own farm in Los Angeles where they grow most of their food. She enjoys getting her kids involved in the farm-to-table process, such as harvesting honey from their seven bee hives. 

"Kids will say, 'I don't like broccoli, I don't want broccoli,' but if we're picking it fresh out of the ground and eating it in the row of the garden, they can't resist it," Garner told People. "You can't resist what is still warm from the sun. You just can't. So all of the luck that I've had with my kids, is what's been picked with the dirt still on it and what's been plucked out of the ground, rubbed on your knee and eaten right there."

It's clear that Garner's dedication to a well-rounded, family-oriented, fitness-focused lifestyle has paid off — and we can't wait to see the mom of three kick ass in her upcoming role. 

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