Hundreds of pounds more.
But he didn't want to fall victim to his own body any longer, so he started participating in athletic competitions.
He worked his way down 300 pounds and up to overcome an impressive ride.
"Why would anyone want to get on a bicycle in 100 degree heat and take off and complete this thing? It was something I couldn't even grasp."
That is what was going through Mac's head when he was hundreds of pounds heavier.
A student at MSU, Mac and his wife ended up living in Wichita Falls after graduation.
"I lived here in Wichita Falls for 10 years and when I lived here in Wichita Falls, I gained about 150 pounds here in this city," he says. "And to remember back then what the Hotter 'n Hell was was just way over my head."
But now, Mac is back and he looks a bit different than he did before.
"I was sick and tired of not being able to do things that I wanted to do," Mac says. "I would be stuck in the vehicle during vacations when my wife and kids were running off and having a good time, or I'd be trying to get out of things that had any type of physical activity to it."
At his heaviest, he tipped the scales at more than 530 pounds.
Thanks to a healthier lifestyle, he's down 300 pounds, weighing in at about 230.
And he's ready to tackle the ride that once seemed impossible.
"So coming back now and being part of this race kind of has that cyclical completion of this journey that I'm on," Mac says.
It's a journey he hopes will inspire others to get in motion toward a healthier lifestyle.
"Mac" is using his story to help raise awareness about the dangers of childhood obesity.
To learn more, go here: http://www.ymcafw.org/inspiration.aspx
Copyright 2015 Nexstar Broadcasting, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.