Charlie Sheffield,57, of Alpharetta, Ga. lost 82 pounds

Pounds lost: 82 pounds

Height: 5 feet 9 inches

Age: 57

How long he's kept it off: "I began my weight-loss journey in the spring of 2003," says Sheffield. He reached his goal in 2011 and has maintained his weight since.

Personal life: "I live in the North Fulton Alpharetta area. My wife, Pam, of 30 years and I have an adult son that lives in Canton," he says. "This passion for fitness and health led me to begin my own personal training, nutrition and weight-loss company (www.urfitnessguy.com)."

Turning point: "I have struggled with my weight most of my adult life," he says. "I would lose a few pounds and then gain back the weight I'd lost and usually more back as soon as I stopped the diet I was on," he says. "If there was a diet out there, I tried it … As soon as I began actually thinking about what I was eating, I immediately began to lose weight."

Diet plan: "I developed my own plan by taking the good and bad from all of the weight-loss programs that I attempted. I developed a simple nutrition and fitness plan that I found to be sustainable. I usually eat five to six times a day," he says. His day starts with a whey protein drink followed later by an egg white omelet, veggies, berries and a whole-grain tortilla or oatmeal. Lunch is lean protein with veggies, and dinner is lean protein, veggies and a salad.

Exercise routine: "I typically resistance train three or four days a week and perform about twenty to thirty minutes interval cardio most days."

Biggest challenge: "I was my biggest challenge," he says, until "I stopped being on a diet and started focusing on healthy eating, exercise and stopped worrying so much about how much weight that I had lost. Also, not beating myself up or feeling guilty when I don't eat healthy. Events in our life happen where we're not going to be able to eat healthy. So I deal with that single event, don't let it steamroll and move on."

How life has changed: "The biggest change in my life is that I became so passionate about fitness and health that I became a certified personal trainer," he says. "I'm not a bragger, but a single event really changed how I thought about myself … One day, my trainer said that some of the folks at the studio told her that they wanted to be built like the buff guy in his 50s. I was floored when she said that they were talking about me. Until that day I (still pictured) myself as being overweight. My true passion has always been in helping others. I felt an obligation to share my knowledge so that others do not have to suffer through all of the struggles that I encountered."