One afternoon just three years ago, Erica Lugo was sitting on the couch watching her then-3-year-old son, Connor, play on the floor. But when Connor asked if she could come down and join him, she promptly responded "no" — at 322 pounds, Lugo was too tired to move from her spot on the sofa.

"That was a huge wake-up call for me," Lugo told TODAY. "Oh my gosh, I told my 3-year-old son no I couldn't play with him, because I was too tired to get off the couch."

That realization was just what Lugo needed to jumpstart her weight-loss journey. Knowing it was time to get her health back on track, the young mom downloaded an app that helped her track calories and exercise. She had always struggled with her weight and developing a true understanding of nutrition and fitness, but the app made things easier — and the goals it helped her set are refreshingly realistic.

For the first 13 months of her weight-loss journey, Lugo followed the app's recommendations to eat 2,000 nutritious calories per day and work out four times per week. With the help of smaller portions, low-cal frozen dinners, and short 20 to 30 minute workout sessions, she dropped the first 122 pounds. Sounds almost shockingly simple, right?

"When I first started, I had no idea what to do," Lugo said. "The basics are what worked."

When Lugo's weight loss plateaued after those first 13 months, she made some adjustments to her diet and exercise routine and was able to lose another 38 pounds. Now, Lugo weighs in at 162 pounds — and she's gained a muscular physique that she's super proud of. (As she should be!)

Today, the 30-year-old maintains her impressive 160-pound weight loss with hour-long workout sessions five or six times per week, during which she spends 20 minutes doing cardio and 40 minutes lifting weights. She also follows a healthy, well-balanced diet, though she does indulge in a cheat meal (think: doughnuts, pizza, or a cheeseburger) once a week. She continues to document her food and fitness routines on Instagram, and FYI — Connor is his mom's biggest cheerleader today.

Ultimately, it was a few simple changes (and viewing her weight-loss journey as a lifestyle transformation, not a quick fix) that helped Lugo peel off the pounds. Her best advice for others who want to follow in her footsteps?

"You don't have to have any reason [to lose weight] other than being healthy," Lugo said. "Your body is such an important thing and you get one in your life; you better treat it well."

[h/t TODAY

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