Published Thursday, January 26, 2012 4:21PM EST
Last Updated Wednesday, August 8, 2012 4:30PM EDT
Julie Horner was so overweight she couldn't walk the two blocks to her mailbox, until her doctor gave her a wake-up call.
The 320 pound woman was told her daughter would be motherless if she didn't make some changes, so Horner joined a gym – first walking on a treadmill, then joining a fitness class.
"I'd been watching it for a couple of months and wanting to go in, seeing the group of people outside of the room and wanting to be one of those people," she said. "One day I went for it and I thought maybe I'll hide in the back corner and maybe nobody will notice me."
Horner stuck with it and is now wearing her smallest size of clothes since she was 12, inspiring her husband and parents to get fit alongside her.