Ruth Bader Ginsburg has 'at least 5 more years' on the court — here's how she stays fit at 85, according to her personal trainer

Ruth Bader Ginsburg, associate justice of the U.S. Supreme Court.
Andrew Harrer | Bloomberg | Getty Images

Supreme Court Justice Ruth Bader Ginsburg may be 85 years old, but the gender equality advocate and Clinton appointee is still looking forward to years of practicing law, she suggested Sunday.

"I'm now 85," Ginsburg told CNN July 29. "My senior colleague, Justice John Paul Stevens, he stepped down when he was 90, so think I have about at least five more years."

With frequent swing-voter Justice Anthony Kennedy's retirement effective Tuesday, and two of the four remaining liberal-leaning Supreme Court judges now the oldest on the bench (after Ginsburg, Stephen Breyer is 79), President Donald Trump's vow to nominate conservative (and pro-life) justices has caused Ginsburg's staying power and tenure to be widely discussed.

And according to personal trainer Bryant Johnson, with whom Ginsburg has worked out for nearly 20 years, she is showing no signs of slowing down.

"She is like a machine, she keeps going, she keeps going," Johnson, who trains the the judge for at least an hour, twice a week, tells CNBC Make It. "She can come in there with only one hour of sleep, or two hours of sleep, and she is still committed to doing the work out." (Ginsburg is known to be a workaholic who toils into wee hours.)

Indeed, Ginsburg is not a morning person, Johnson jokes, so the pair meets around 7:00 p.m. to work on strength exercises and cardio. Usually their work outs are "just in time for the 'PBS NewsHour,'" which plays in the background.

As chronicled in Johnson's book "The RBG Workout," her routine includes "full-strength planks, push-ups, chest and shoulder presses, bicep and leg curls, one-legged squats and knee raises," says Johnson. "Pull downs, cable-rows. Inner- and outer-thigh. Glute work."

But Johnson says the most impressive element of exercising with the two-time cancer survivor and octogenarian is her determination and commitment.

"There is no excuse. You either do it or you don't, and that's her attitude. She shows up," he tells CNBC Make It. "We are consistently working out. I look at my schedule, and we match our calendars up maybe a month or two months out, and we actually plan the workouts."

Exercising seems to help her stay energized, says Johnson, a benefit which many successful people, like Mark Zuckerberg and Richard Branson, point to.

"She seems to have more energy after we work out," Johnson explains, "probably because she gets to unplug from thinking about the law. She's just working out. It gives her brain time to rest and recharge."

When Johnson heard of Ginsburg's plans to keep working for another half-decade, he says he wasn't too surprised.

He tells CNBC Make It he thought to himself, "So she's going to work five more years? Looks like I know what I'll be doing."

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ConBody CEO Coss Marte shares the journey that transformed his body and his life
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