She once weighed 400 pounds. Now she’s a muscular Miami marathoner and inspirational coach

The last time Kristen Smith registered 405 on a scale was in 2005 in a truck full of corn at her uncle’s farm in Iowa.

It wasn’t the corn’s weight.

“We were at a grain elevator,’’ said Smith, 45, who was 27 at the time. “I got out of the truck and saw the receipts of how much the truck weighed with the corn and me — and without me. I just hoped my uncle hadn’t done the math.’’

Today, Smith, a certified fitness instructor, personal trainer, sports nutritionist and former body builder, carries 165 pounds on a muscular, 5-9 frame and will run in her fifth 26.2-mile race at 6 a.m. Sunday in the Life Time Miami Marathon.

Five of Smith’s students from her popular Miami Beach Fit Camp, held every morning at sunrise on the 64th Street beach by Miami Beach’s Allison Park, will join her in the marathon event that includes a half marathon and reached its 18,000 capacity in September. All six, including Smith’s husband Roy Jeter, will start in the same corral on Sunday, then break off into their separate distances until they meet again after everyone finishes.

Smith first did the Miami event’s half marathon while vacationing in 2020 and fell in love with the course that starts before the sun rises on Biscayne Boulevard, heads over the MacArthur Causeway past lit-up cruise ships, along Ocean Drive in South Beach and back over the Venetian Causeway into downtown for the finish. The marathon distance proceeds into the Brickell and Coconut Grove areas before returning to the same finish area.

“I never run one minute of my life anymore without basking in the fact that I’m actually doing it,’’ Smith said. “I was 400 pounds. And before that I was 350, and before that, 300... I was fat my whole life and sedentary my whole life. So whenever I move my body in any way it’s still exciting.

“Marathons require mental toughness to endure the boredom and the pain. I can’t be an Olympian, I’m too old for a lot of things, but I can keep my feet moving for four or five hours.’’

Life Time Miami Marathon race director and co-founder Frankie Ruiz believes that running a marathon, “besides providing a specific goal for someone or a group of friends, almost begs you to adopt a healthy, sustainable lifestyle, not just an arbitrary ‘I want to lose 10 pounds’ or ‘I want to run a marathon’ goal. And it helps to do it with others because you’re committed to something bigger than just yourself.

“I love when people say they’re not hard-core runners. I appreciate the 20 to 30-percent that call this their everything — the ones that wear short-shorts, are 8-percent body fat, run all the time. But the rest of the population that runs races falls into a much bigger bucket, and probably an even more inspiring bucket. That inspiring bucket is what the world really is. If we can help that group use our marathon as a tool, that’s awesome.’’

Fit camp

Smith’s fit camp, which has 50 members and averages about 20 students of all ages and fitness levels on any given day, does high-intensity interval training that is tailored for each ability and includes different activities to keep it fresh. She relishes the concept of no mirrors and being outside while the ever-changing hues of a Miami Beach sunrise provide serenity that other classes rarely afford.

“We always start with running down to the water, arms overhead, clearing your mind and setting your intentions for the day,’’ Smith said. “Leave your life in the parking lot,’’ Smith tells her students. “You’re here to spend time with your body and yourself.’’

Smith and her students have become close and share in several activities outside of class. Running is just one of them.

“That’s what makes this different from other exercise programs in a gym or anywhere else,’’ said Danny Martin, 60, a United Airlines pilot who will run his fourth marathon Sunday. “We have a What’s App social network and enjoy each other’s company. In a lot of places, you feel like people are judging or criticizing you. There isn’t any of that in this program.

“Kristen doesn’t focus on if you’re young or old or big or small. She’s always positive and encouraging and enjoys all of our differences. She radiates.’’

Smith, whose best marathon time is 4 hours 30 minutes at the 2019 Twin Cities Marathon in her former home of Minneapolis, knows all about judging.

She said she grew up with her brother and sister and parents in an “evangelical, religious cult in the suburbs of Minneapolis.”

“We dressed like ‘Little House on the Prairie,’ very fundamentalist, very sheltered, no exposure to the outside world. Everything was a sin except eating.’’

Smith said her father was a janitor, and her parents and siblings didn’t live with other church members, but also didn’t associate with anyone outside the church. The children were home schooled.

“My generation, we were all like, ‘Screw this,’ and got out when we grew up. So, the cult dissolved. The last few years there has been a lot of healing and understanding,’’ she said of herself and her siblings. “We weren’t sexually abused so it could have been a billion times worse. But did it affect us? Yes.’’

Losing weight

Smith said she began her 240-pound weight loss in 2006 after her sister asked her to be in her wedding. She lost about 100 pounds through 2008 by making small changes. “When you’re 400 pounds you need to eat a lot to stay 400 pounds,’’ she said. “I ate 24 hours a day. So instead of eating two stuffed crust pizzas on the couch at night, I’d switch it to two thin-crust pizzas with just ham instead of all the meat. Or instead of three subs at Subway with meatballs, I’d switch them to turkey.

“I tried every diet there is, and learned something from all of them.’’

Smith said she stayed at 300 pounds for a long time after giving birth to her son, Steven, now 25. Back-to-back video clips of her holding her 1-year-old son when she was morbidly obese and 22 years later in a bikini holding him as a grown man, went viral.

“It was very redemptive,’’ she said.

Smith underwent gastric sleeve surgery — “They removed a large portion of my stomach’’ — when she weighed about 280 in July 2011 and lost 80 pounds in six months and first saw the “199-pound breakthrough” in early 2012. In 2013, she said she started gaining the weight back, then began a running regimen and studying nutrition. By 2014, she was strength training in a CrossFit gym.

She moved on to “extreme’’ things, Smith said. “One year no fast food and no drive-throughs. Another year no chips. The next year no doughnuts or popcorn.”

She had three separate skin removal surgeries in 2019 and 2020, continued her fitness and training regimen, quit her job as an accountant for a patent law firm and moved to Miami Beach several months after the half marathon. She created her class — formerly known as the Miami Beach Boot Camp — in November 2020.

These days, Smith said she eats “real, mostly single-source foods.’’

“I tell people to eat an apple, a banana, a piece of chicken — foods that don’t have a marketing department are what you should be eating,’’ she said. She doesn’t drink alcohol and mostly eats “meat, eggs and vegetables” and drinks “a lot of water and coffee.’’

The students

Three of Smith’s students have opted to run the half marathon.

Malinda Walsh, 46, a Miami Cancer Institute nurse, has attended the fit camp class for three years.

“What was shocking to me was when I first saw Kristen on the beach she had been preparing for one of her bodybuilding shows,’’ Walsh said. “She was really lean and this bubbly, blond, beautiful woman. My first really catty feeling was, ‘What does she know? She has never really had to struggle.’

“I went on her website, saw the before pictures and her transformation, listened to her podcasts and realized how long her journey had been. With Kristen, it’s not just exercise for the body, but exercise for the soul.’’

Bonnie Graham, 42, a lawyer in Smith’s class, will attempt her first 13.1-miler Sunday. “I didn’t know about Kristin’s backstory for probably a few months,’’ Graham said. “When I saw her previous pictures, my jaw dropped. I was like, ‘This isn’t the same person, is it?’ Probably, some of her story contributes to her ability to meet you where you are without ostracizing or making you feel bad. She’s amazing.’’

Nadina De Castro, 54, a Miami bank accountant who has lost 90 pounds since joining Smith’s class in May 2022, will also run the half marathon. “If I get tired, I’ll walk. If I get tired of walking I’ll take an Uber,’’ she said, laughing. “Nothing will impede me.’’

And nothing is likely to impede Smith, who has kept her excess 240 pounds off and has no intention of going back.

Her mission, she said, is “to fire up the whole world to get up and take care of themselves for the sheer joy of it. I never imagined I could be a normal person again. Feeling good in your skin and being able to move feels so much better than feeling stuck. I wish everybody knew how good it feels.’’

If you go

▪ What: Life Time Miami Marathon and Half Marathon

▪ When/Where: 6 a.m. start Sunday, Jan. 28, on Biscayne Boulevard outside the Kaseya Center in downtown Miami; Finish is a bit down the street adjacent to Bayfront Park. There are bleachers for spectators on Biscayne at the finish.

▪ Who: Combined field of 18,000.

▪ Expo: 12 to 7 p.m. Friday and 10 a.m. to 6 p.m. Saturday at the Miami Beach Convention Center, 1901 Convention Center Dr., Miami Beach.

▪ Registration: closed. Race sold out.

▪ Note: To learn more about Kristen Smith’s Miami Beach Fit Camp, visit MiamiBeachFitCamp.com