Getting older shouldn’t mean slowing down. In fact, by keeping active you can actually slow aging in your body's cells to stay young, according to a 2017 study in Preventive Medicine. The only problem: Finding motivation to exercise is a major struggle for many of us.

Enter these five fitness heroes, who are all 70 years or older. Sure, it’s motivating to see 40- and 50-year-olds getting in the best shape of their lives (like this woman who went from not being able to do a push-up to winning the CrossFit Games), but meeting seniors who are jumping hurdles, powerlifting at the gym, and competing in IRONMAN triathlons is next-level inspiration. And that’s exactly what these amazing women are doing.

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Every year at Prevention, we meet countless people who are busting expectations of what it means to stay fit at 70, 80, and beyond—so it was tough to pick just five stories from 2017 to share. Needless to say, we think these strong women will provide more than enough motivation to get you moving.

The Track & Field Star: Flo Meiler, 83

If you think high jump and shot put are best left to high school athletes, you haven't met Flo Meiler. The 83-year-old from Burlington, VT, started competing in the National Senior Games at age 57 and has set 20 U.S. records in track and field since then. And she never stops pushing herself. For instance, at age 65 she took up pole vault, then set an age-division world record in the event when she was 80. "I've injured myself from time to time," she told Prevention. "Eight years ago, I ended up with 10 stitches in my left leg after hitting a hurdle—but trying new things keeps me young."

Read Flo’s full story here.

See Flo in action:

preview for Fit at 80: The Track & Field Star

The Yoga Instructor: Janice Lennard, 74

A former professional dancer, Janice Lennard, 74, has always led a super-active lifestyle. About 14 years ago, though, she got certified as a yoga instructor to helps others do the same. Lennard, who practices yoga 30 hours a week, recently had a total hip replacement and is up-front about the limitations our bodies face with age, but she's of the firm mindset that regularly doing some exercise (even the gentlest of stretches) can make a huge difference in how you feel. "You know, it’s easier to do nothing," she told Prevention. "So I think when we get older and have that as an excuse, we do less. But just a half hour or hour—stretching on your own or with a class—shows you the benefits and gets you going. And then you don’t want stop and it becomes a habit."

Read Janice’s full story here.

MORE: Over 40? You'll Want To Do These 5 Exercises Every Week.

The Personal Trainer: Nancy Burnham, 70

Nancy Burnham is proof that it's never too late to turn your health around. Just a decade ago, her doctor warned her that she had two prolapsed heart valves and would need more meds to keep her blood pressure in check. That was all she needed to hear to hit the gym for the first time in her life—at age 61. (Prefer exercising outside? Here's how to walk off weight after menopause.) Through regular workouts with a trainer she dropped 30 pounds and reversed her heart disease in just a year. By age 65, she got certified as a personal trainer with the American Council on Exercise so she could help others over 55 improve their quality of life. "I’ve been called to do this work, and I love it," she told Prevention. "The universe gave me a second chance, and the least I can do is give other people that joy and capability that I’ve been given myself."

Read Nancy’s full story here.

The Triathlete: Sister Madonna Buder, 87

This Catholic nun has a competitive streak. She's tackled more than 340 triathlons since age 52, including 45 full IRONMANs. (An IRONMAN is 2.4 miles of swimming, 112 miles of cycling, and 26.2 miles of running.) Oh, and did we mention Sister Madonna is also the oldest person to ever finish one of these beastly triathlons? "During an IRONMAN, when I reach the point of feeling utterly wasted, I'll think of people I want to pray for, and that carries me through," she told Prevention. "I pray for anyone who pops into my mind and ask the blessed Mother to love and protect them. It really keeps my mind off of me and helps the miles fly by." (You need to read the inspiring stories of two IRONMAN competitors over 40 who made it to the World Championship in 2017.)

Read Sister Madonna’s full story here.

The Marathoner: Kathrine Switzer, 70

In 1967, Kathrine Switzer became the first woman to officially enter and run the Boston Marathon—before the iconic race allowed women to participate. She registered under "K.V. Switzer," so nobody knew a woman had signed up until they saw her (and the race director chased her down) on marathon morning. This year, to commemorate the 50th anniversary of her controversial debut, Switzer ran the Boston Marathon again with the same bib number she wore in her first. "People still treat older people the way they treated us women 50 years ago, which is, 'Be careful! You might hurt yourself!' when in fact the opposite is the case," Switzer told Prevention. "The more you do, the more you can do! There are lots of women who have run marathons at 70, 80, even 90. I was only eighth in my age group at Boston [in 2017], for heaven's sake!"

Read Kathrine’s full interview here.

MORE: If You're Over 40 And About To Start Running For The First Time, Here Are 8 Things You Need To Know