Helen Costa-Giles, a mom of two boys, lost 90 lbs. after a health scare by cleaning up her diet and taking up weightlifting

Credit: Gary Giles; Geronimo Rodriguez

At her yearly medical checkups, Helen Costa-Giles would nod along as the doctor told her she was in the “morbidly obese” category and insisted she lose weight. She would try weight loss pills and low-carb diets, but it would never stick — until 2014, when at 220 lbs., her doctor told her she was headed for major chronic health problems.

“My numbers were really off the charts and it scared the life out of me,” Costa-Giles, 38, tells PEOPLE. “That was exactly my turning point.”

The mom of two boys had watched her own family members deal with health problems from poor eating habits, and she didn’t want her sons to witness the same thing.

“I had to break that cycle, because it was up to me to lead them to a healthier lifestyle,” she says. “I basically came down from the doctor’s that day and I had my paperwork and I slammed it down on the kitchen counter and said, ‘That’s it. We’re done. No more yo-yo dieting, no more fads.’ ”

Helen Costa-Giles
| Credit: Geronimo Rodriguez

Costa-Giles immediately rid the family’s pantry of any processed or preservative-filled foods, “and we were literally left with no food,” she says. “And then we had to get groceries because we didn’t have anything in the fridge!”

For 30 days, she ate only “100 percent clean” foods, and spent hours every Sunday prepping healthy meals like vegetable-filled omelets for each day of the week. Those first days were “really hard,” but she started getting her energy back and saw her weight drop. She adjusted the diet slightly to include meal replacement shakes and cut down on her prep time, and in six months she lost the majority of her weight.

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Costa-Giles was tracking her progress with weekly photos and soon decided it was time to hit the gym.

“My body reacted very quickly to weightlifting, and I started to lean out,” she says. “The scale wasn’t making huge differences, but the inches were changing. I kind of got obsessed because for the first time in my life, my body was actually doing what I asked it to do.”

Helen Costa-Giles
| Credit: Geronimo Rodriguez

She added HIIT training and Spartan Races for endurance, and eventually lost a total of 90 lbs.

Costa-Giles even started her own free workout classes — out of her garage in San Antoinio, Texas — four days a week at 4 a.m.

“My passion is to make it a movement,” she says. “We actually moved out of my garage because we got too big. We call it the No More Excuses Lifestyle. And some of these people don’t need to get up at 4 a.m., but they get a boost from the energy level of the other people. Some of them come and then go back to sleep!”

Costa-Giles, who also works full-time as a supervisor in automotive distribution, says her story shows that anyone has the time to lose weight — she’s even helped her husband drop 60 lbs.

Helen Costa-Giles
| Credit: Geronimo Rodriguez

“I have two kids and a full-time job,” she says. “I know many people don’t start their fitness journeys because they have too many excuses. I like to share my story because it’s so relatable.”

And now, with her muscle-bound body, Costa-Giles is proud.

“I’ll be honest, I love everything about me. And that’s the first time in my life that I’ve been able to say that,” she says. “I take so much pride in every inch of my body because I know what it’s been through.”