Onetime workout guru Jane Fonda isn't letting age slow her down

At 80, Jane Fonda has a body that can still make jaws drop almost 40 years after she launched her 1980s Jane Fonda’s Workout empire. In the new issue of PEOPLE, the actress, activist and author credits her looks mostly to being “lucky” — but says she continues to exercise both her mind and body on a regular basis.

“If I had a dream day it would be spent hiking in Will Rogers [Historic State Park] and I would come back and work out and then I would read all day long,” she says.

In her books, Fonda has said she’s a fan of Pilates and resistance bands — and of getting eight to nine hours of sleep a night. “Maintaining a healthy weight, strong heart and bones through regular physical exercise is a major ingredient for successful aging,” she wrote.

For much more from Jane Fonda, pick up this week’s issue of PEOPLE.

Posing for Jane Fonda’s Workout video in 1982.
| Credit: Courtesy Everett Collection

She also has been open about the plastic surgery she had at age 72 on her jawline and under her eyes. “I finally got tired of looking tired when I wasn’t,” she wrote in her book Prime Time.

But despite still turning heads on the red carpet, Fonda is much prouder of how she’s changed beneath the surface.

“I’m thankful that I’ve gotten better over the 80 years,” she says. “I’m less judgmental. I’m forgiving. It wasn’t always true. I’ve really worked hard to get better as a human being.”

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She is also extremely thankful to not only be be healthy and happy but also busier than ever.

She received Emmy and Screen Actors Guild Awards nominations this year for Grace and Frankie, her Netflix comedy with friend Lily Tomlin. In September, she teamed up with Robert Redford for the fourth time for the romantic drama Our Souls at Night. Next up, she will star in the comedy Book Club with Diane Keaton and Candice Bergen. And she continues her activism and charity work, including with the organization she founded, the Georgia Campaign for Adolescent Power and Potential, which supports health, well-being and pregnancy prevention for teens.

“I didn’t think if I did live this long, that I would be vibrant and healthy and still working,” she says. “I’m grateful.”