The journey hasn't always been easy. During his running and training earlier this year, he tore a meniscus in his left knee.
"I was scared to death -- if I couldn't work out, the old me would pop back out," he said.
His surgery was on a Thursday. By Monday, he was back at the gym, working on his upper body, chest and shoulders.
Two weeks later, he was walking on the treadmills. At three weeks, he was able to jog, and by the fourth week, he could run again.
Beyond the numbers on the scale, McCarty has seen many benefits to his weight loss.
Remember how he agonized over a running a mile in 22 minutes in August 2012? In June, he ran a 5K race (3.1 miles) in under 28 minutes.
After he crossed the finish line and saw his time, "I just started crying," he remembers. "I just kept walking and thinking about where I came from."
At his job, he's noticed a change as well. He's always had to be on his feet all day, but because of his weight, he used to avoid tasks involving standing on ladders and leaning or reaching -- he was scared he would fall.
"Now, I'm like a little ninja up there," he said. "I can reach over, and I don't care about falling no more."
Weight loss contests at Downsize Fitness proved lucrative for McCarty. He originally had no intention of winning the first round, from September to December, but when he learned he was close, he stepped up his workout to four hours a day, five times a week. That earned him $7,000.
The January to June phase, which came with a $20,000 prize, was an incentive to keep going with his weight-loss efforts. After winning, he paid off his truck and bought his wife a nice camera; the rest is in savings.
He has since kept off the weight, but the gym won't be doing more of these contests, a spokeswoman said.
Keeping it off
McCarty has several more goals to keep himself motivated.
Right now, he's training for a half-marathon that takes place Sept. 14, and in October he'll do a sprint triathlon. His goal for next year is a half Ironman.
He also wants to help the rest of his family get fit. McCarty has issued a challenge: They're all going to run a 5K together in December.
"I don't want to be a hypocrite to my kids and saying, 'You've got to lose weight now,' " he said. "But I am going to challenge them to do this one thing for me. I think they're going to like the results."
Next month, the family is going back to the same amusement park -- Silver Dollar City in Missouri -- where McCarty had to give up his seat on a roller coaster last summer.
Trying to buckle the seat belt then led to unexpected twists and turns in his life. Now, he's ready to experience the full ride.