Marcus Cook, an oil executive, weighed 489 pounds. Competing in anything was out of the question. But this weekend he is taking on the Half Ironman in Galveston.
Cook said, "I think still my goal is not to twist my ankle, not to drown and not to get ran over by a car."
ABC13 first introduced you to Cook earlier this year at the Chevron Houston Marathon.
Meet Marcus Cook: Marathoner cheats death, loses 250 pounds
Cook's story is not only about his success.
"I started realizing that I hurt my whole family. And me becoming healthy made me realize that my family wanted to be healthy," said Cook.
Cook's path to a healthier life inspired his family, including his 14-year-old son Jackson who has lost 80 pounds since August.
Jackson recalled knowing he was ready to make a change when he realized he was too big to move his arms fully.
Jackson said two things kept him motivated to lose weight -- seeing an unflattering picture and something a friend said. "My friend, he put his hair up funny, he was like being funny. I said, 'Hey, what's up with the hair?' He said, 'Hey, what's up with the extra skin?'"
Jackson is now competing alongside his father.
The teen completed his first marathon in Seabrook recently. Jackson admitted, "I didn't wanna be like my dad, that 500-pound man."
Together, this Tomball family has also changed the way they eat, avoiding meat and eating a plant-rich diet.
Cook's change has trickled down.
Cook said, "Losing my weight has changed the DNA of my entire family. It's rubbing off on everybody, and it's for the better."
The Half Ironman is set to begin Sunday morning in Galveston.
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