7 Ways Catherine Zeta-Jones, 55, Stayed Fit for Viral "Birthday Suit" Photo

1. She Absolutely Loves To Play Golf

Zeta-Jones loves to golf with her husband, but admits she struggles with motivation when it comes to the gym. “I have to work out. Do I want to work out? No,” she told Vogue Australia. “Do I really want to walk around the corner to the gym? No. I want to go for a spa day, but I have to exercise. I play golf. [Now] we’ve just moved back to the city; when I lived in Bermuda I used to swim every day. I haven’t been swimming for ages. I’m supposed to go three times a week.”

2. Turn Up the Music

Zeta-Jones says her favorite workouts are golf, swimming, tennis, peloton, her home gym and tap dancing. "I have a ballet barre in my gym,” she told Prima. "I turn the music up so loud that the walls are pulsating, and I go for it for an hour. I also hula-hoop, walk on the treadmill, do the elliptical [machine]. I try to keep the whole body working."

3. Breakfast Is a Non-Negotiable

Zeta-Jones is not someone to skip breakfast, ever. “I always eat breakfast; I’m not one of those people who can skip it,” she told the Wall Street Journal. “I have a go-to breakfast that happens every day. Right now, I’ve just switched. In the winter months, I have porridge with banana, brown sugar and berries. Come daylight savings, when we spring forward, I switch to my nonfat Greek yogurt with my berries and my granola. I was brought up on hot porridge in the winter when I was growing up in Wales. And as soon as the clocks go back in September, I start porridge, and as soon as the clocks go forward, I start granola.”

4. Here Are the Supplements She Takes

Zeta-Jones takes supplements to support her health and fitness. “I have a plethora of vitamins in my cabinet in my bathroom,” she says. “I do take vitamin D and vitamin B whenever I can. But I eat very healthily. Of course, I have my french-fries fixes and my chocolate, which are something I just love, and I just have to have them. But I try and get as many nutrients in as possible. But when I get really old, I’m going to start taking a lot of vitamins because I only want to be able to eat dessert for the rest of my life. I only actually eat real food because I have to right now. My dream is to only eat desserts, ever. It’s a goal.”

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5. Beauty Sleep and Napping

Zeta-Jones swears by sleep for helping maintain her beautiful looks and supporting her fitness. “[I relax] by reading and sleeping. I like to sleep. If I had the chance to, I would have a nap everyday. Sleep is a big beauty tip. I have to have eight hours to function.”

6. Living the (Mostly) Quiet Life

Despite her social media activity, Zeta-Jones says she enjoys a very quiet life with Douglas. “We both are predominantly quite quiet and very private people, but we have the ability to be able to go out and go to dinner,” she told InStyle. “This is Catherine on the red carpet… This is my lovely husband Michael on the red carpet. And then we go home and close our doors. And we have a very simple existence where we just hang a lot, and we have a lot of interests.”

7. Confidence With Age

Zeta-Jones becomes more confident in herself with every year that passes. “Something about getting older was that I don't take a lot from people,” she told InStyle. “I just don't take it, and I don't take it in a very gracious way. And it's only something that comes from experience and it's only something that comes from being 53. But I really feel now that there's a different chapter ahead of me, and it's exciting to see what happens next. My dreams have come true, and everything else now is a bonus for me.”