Watching him warm up, you could easily mistake him for a seasoned athlete. But you would be wrong.
At the age of 37, he is actually a recent recruit in the army of fitness.
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His weigh ballooned dangerously out of control while working from home during the COVID-19 pandemic.
"I was at my highest, 330 pounds, exactly a year ago," he said. "I was developing hypertension. I was borderline diabetic."
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Growing concerned, his mother pleaded with him to make a change.
"It all started with a promise to my mother," he said. "When she saw me a year ago, she said, 'You really need to start watching your weight and your health.'"
He consulted with a doctor, signed up for a weight loss program, and in an extraordinary achievement, he lost more than 150 pounds in the first six months by changing his diet and through low-impact cardio.
It wasn't until this past August that he was introduced to running by his fiancee.
"First I started with 5Ks on the treadmill," he said. "Then it was time for me to move up to the 10K, and now, I'm running a half marathon."
Seeing his health improve kept him going.
"I was really motivated," he said. "To see the changes in my body as I was progressing over time, I think that's what kept me motivated."
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But for Valencia, the drastic lifestyle change wasn't necessarily about looking thinner.
"To be frank with you, I was very comfortable in my own skin," he said. " Whether I was morbidly obese or now in my current physical state, I don't think it was so much about aesthetics. It was more about health. It was more about being more active and extending my lifespan."
He said he felt an instant connection with running, and now, his health journey is inspiring others.
"I have people who have seen my changes, and they want to replicate that effort," he said. "It takes effort. It takes sacrifice. But it's worth doing it...All the health benefits that come with it, I think are just amazing. It's such a rewarding experience being able to run, being able to feel healthy."
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