WATCH: Ruth Bader Ginsburg's personal trainer does 3 pushups in her honor

RBG working out with Stephen Colbert

Supreme Court Justice Ruth Bader Ginsburg was known for her determination to staying in shape, despite numerous bouts with cancer.

Ginsburg's personal trainer of more than 20 years, Bryant Johnson, paid a special tribute to her as she lay in state in the U.S. Capitol Friday, by dropping to the floor and doing three pushups before her casket.

Johnson wrote a book about it in 2017, "The RBG Workout: How She Stays Strong...And You Can Too!"

Ginsburg continued her workouts until she was 87. She died after a long battle with pancreatic cancer.