Denise Austin was stunned when Sports Illustrated Swimsuit asked if she would walk down the runway in a bikini.

The fitness icon joined her daughter, SI Swim model Katie Austin, at the 2022 Sports Illustrated Swimsuit Runway Show in July. The mother and daughter proudly rocked two-pieces on the catwalk for the live broadcast show at the W South Beach pool in Miami Beach, Florida.

"At first, I thought, ‘Am I really doing this? Are you kidding me? In a bikini at age 65?’" Austin chuckled. "But how exhilarating that was! It was this amazing, natural high. It was an honor that they even asked me. And then to do this with my daughter made it even more special. It was the highlight of my life to walk the runway with my daughter. I’m still not over it."

Denise Austin SI Swimsuit Runway Show

Katie Austin (left) and Denise Austin walk the runway for Sports Illustrated Swimsuit Runway Show During Paraiso Miami Beach on July 16, 2022, in Miami Beach, Florida.  (Photo by John Parra/Getty Images for Sports Illustrated Swimsuit)

The former gymnast shared that her daughter, 28, has been an inspiration to her.

"It brought tears to my eyes [when I first saw her in SI]," Austin explained. "I was just so proud of her. She’s just the sweetest person with the biggest heart. And she’s a hard worker. She tried out for it three different years through Swim Search, so it’s not like this was given to her. And I’m just so proud, because this has been a dream of hers. I remember seeing Christie Brinkley and Kathy Ireland on the cover and [thinking] how that was such a big deal. So it’s amazing to see my daughter in the magazine. And she will now always be a Sports Illustrated Swimsuit model."

For more than 30 years, Austin has been encouraging people to kick off an active lifestyle through her workout routines. She has sold more than 24 million exercise videos and DVDs. She also led the longest-running fitness show in TV history. She is still bursting with energy and enthusiasm while doing a "total body burn cardio" or training to be "lean, toned and totally fit" – all with a megawatt smile.

Denise Austin Katie Austin

Katie Austin (left) and Denise Austin pose backstage for Sports Illustrated Swimsuit Runway Show During Paraiso Miami Beach. (Photo by Alexander Tamargo/Getty Images for Sports Illustrated Swimsuit)

Most recently, she teamed up with Easy Spirit to launch a new collection on Sept. 15 named "Easy Spirit x Denise Austin." It features active footwear designed for high or low-impact workout routines.

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"Shoes are the most important thing you need whether you’re walking or doing any form of fitness," she explained. "When Easy Spirit asked me to collaborate, I was so excited, because I love their shoes, but I also wanted to make a more fun style with benefits. One shoe is great for power walking that’s also very lightweight… the other is for walking fast or running. I created both styles, but I walk at least 35 minutes a day. I wanted something where I can go out and walk my dog, casually wear to Pilates, or just for running errands. I’m always in athletic wear, so it made sense."

Austin said that low-impact workouts often get overlooked, but there are plenty of benefits for those needing some motivation.

Denise Austin Easy Spirit

Denise Austin and Easy Spirit teamed up for a collection that dropped on Sept. 15. (Easy Spirit)

"You could burn calories and get yourself healthy without putting pressure on the joints," she shared. "It’s easier on your knees, your hips, your thighs and back. I recommend a brisk walk, not a power walk… I also do low-impact aerobics at home. So instead of a regular jumping jack, I will do a heel jack where you’re not jumping. The larger muscles of the body burn more calories, so you can burn more if you use your thighs and gluteus. You don’t need to jump to feel it and get your heart rate up."

According to Austin, her secret to feeling and looking youthful is surprisingly simple. She works out 30 minutes daily and eats balanced meals consisting of "80 percent healthy foods and 20 percent treats," along with drinking plenty of water throughout the day.

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"I like HIIT interval training," she said. "When I’m out walking, I’ll do five minutes of a nice walk. Then I will do a burst of a fast walk where I'm pumping my arms and powering through. Then I do another five minutes of just walking and then take it up higher, almost like a light jog. I also believe in a positive attitude. If I wake up feeling grateful, I’ll want to take good care of myself. And I’ll want to exercise. It’s a message I’ve been preaching for 40 years. I’m still a believer. That’s how I live."

Denise Austin workout

Denise Austin does both high and low-impact workouts daily to stay in shape. (Easy Spirit)

Austin also emphasized experimenting in the kitchen – and eating everything in moderation.

"I love Mexican food!" she gushed. "I love my tacos, guacamole and margaritas. Those are my treats. I come from a big family, and we love to eat. When I go out to dinner, I want to enjoy myself. I don’t even think about what I’m ordering – I just enjoy it. And when I’m home, I do my own cooking. I make food all the time for my family."

The one message Austin has for other women her age is to keep moving.

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Denise Austin Fitness

Denise Austin said her biggest message for women is that "it's never too late." (Photo by John Parra/Getty Images for Sports Illustrated Swimsuit)

"You could always improve your health," she explained. "It’s all about energy level. I exercise for health benefits but also to have the energy to enjoy my life. I’m a true believer that 10 minutes a day will help you get started. Walk for 10 minutes. If you could do that every day, you could improve your spirit and your health."

"I know that exercise is one of the best preventative medicines, so if you could just give yourself 10 minutes, it will make such a difference," she continued. "You can help your mind and your body. And once you do that, you can build yourself up to 30 minutes. And there are all kinds of exercises out there. I like to do leg exercises in the kitchen. I do pushups against the countertop as I wait for my coffee to brew. Every day, I think of ways I can stretch and move more. If there’s one message I can give is that it’s never too late."