Watch 85-Year-Old Ruth Bader Ginsburg Whip Stephen Colbert Into Shape

Supreme Court Justice Ruth Bader Ginsburg is a powerhouse in more ways than one. She’s notoriously tough and steely minded in the courtroom, and, at 85-years old, has an exercise regimen that’s not for the faint of heart. That much was clear last night on The Late Show With Stephen Colbert, during which she whipped the host into shape while wearing her signature Super Diva sweatshirt. “I had reached my decision in the case of RBG versus kicking ass,” joked Colbert at the end of their training session, which included weight lifting, plants, and medicine ball tosses. “Not only can the justice last another five years on the bench—I believe she could’ve killed Tupac.”

And while Ginsburg’s sass and strength have social media buzzing this morning, it’s not the first time her workout has made headlines. “She’s tough as nails, and she’s serious about her workouts,” says her personal trainer, Bryant Johnson, who pulled back the curtains on how she maintains her robust physique in his book The RBG Workout: How She Stays Strong…and You Can Too! last fall to the delight of the Internet.

According to Johnson, who began working with Ginsburg in 1999 following her battle with colorectal cancer, her hour-long, twice-a-week training sessions consist of full-body stretches, jogging on the treadmill, and strength-training exercises, such as chest presses, squats, and push-ups—tackling up to 20 of the arm exercises in one sitting, to be exact. “She gets mad if I try to skip the push-ups,” says Johnson. While her intense workouts are bound to leave people of all ages slack-jawed, there is one revelation that should come as a surprise to no one: Ginsburg insists on playing PBS’s NewsHour during gym sessions. Would you expect anything less from the “Notorious RBG”?

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