Kristen Bell is training BJJ along with her kids: “I could break your arm.”

Brazilian Jiu-Jitsu (BJJ) is a highly effective martial art that focuses on grappling and ground fighting. It also works out the whole body to improve health, strength, flexibility, and endurance.

As a result, there are many celebrities who practice the art. Stars like Demi Lovato, Ashton Kutcher, Anthony Bourdain, and Tom Hardy are some of them. In fact, Lovato just got her purple belt in BJJ two weeks ago.

Actress Kristen Bell recently revealed that she’s also training in BJJ. Bell is famous for many projects; her most recent high-profile role was voicing Princess Anna in the Frozen movies.

She is training in the grappling art under Cesalina Gracie. Gracie is a female empowerment entrepreneur and a granddaughter of BJJ pioneer Carlos Gracie Sr.

Bell said that BJJ is an outlet for her to spend time with one of her daughters. She spoke to Real Simple, where she said the following:

“I started taking mother-daughter jujitsu classes last year with Cesalina Gracie, our trainer, who is the closest physical representation to Wonder Woman you’ve ever seen.”

“I could break your arm.” she joked to the interviewer, feeling confident about her abilities.

She described BJJ as a sport that is “all about leverage” and how you have to be vocal in it.

“It’s about using connection and distance. And doing it with my daughter brought us closer together. The first two classes were about using your voice, because if no one can hear you, you’ll never get any of your wants, hopes, or dreams.”

“You have the right to take up the space that you take up, and to properly communicate with someone—to say yes or no.”

Bell said that the training has done wonders for her and her child. Not only has it been physically beneficial for them, but it has also instilled some social skills in her daughter. Bell said that she even stopped a conflict in her school.

“Yeah, it’s been a ton of growth for both me and my daughter, who was struggling socially before we started, and has come so far and is doing things that just make my heart explode. She stopped a fight on the yard at her school! It’s kind of phenomenal.”