She had lost more than 110 pounds in about 10 months.
"She was ready to take on the world," Candace says. "She wanted to go out and do all these things. ... It was like having our old mom back."
Raiding daughters' closets fun
When she was overweight, Colleen says she never felt bad physically. "I did whatever I wanted to do, but I didn't want to do that much," she says with a laugh.
Today she says she feels "100 percent better."
"She has more energy than we do now," Candace says. "She's just very inspiring, and she just keeps going, and I love her for that."
Colleen was laid off before she jumped on the TreadClimber. She went on multiple job interviews that amounted to nothing. But her first interview after losing the weight resulted in a job offer.
She's not sure if it was her new body or her newfound confidence, but she knows people treat her differently now that she's slim.
"They see you as maybe having something to offer," she says.
Perhaps her favorite part of losing weight is borrowing her daughters' clothes. Before, she hated to go shopping to buy new clothes. Now when she visits, she doesn't even bother to pack -- instead preferring to raid their closets.
Celeste just turned 13, and Candace is happy her youngest sister will get to experience Colleen as the mom she remembers.
"She's very free-spirited and encouraging and happy," Candace says of her mother. "And that was being covered up by all that extra weight she was carrying around."