(CNN) -- Keith Trotter stared at the picture that popped up on his Facebook feed. He felt like the floor was opening up and swallowing him whole.
This photo of himself had been taken a few days earlier at a 2009 New Year's Eve party and posted by his friend Jeremy. Trotter was 386 pounds at the time, wearing size 60 pants, and holding a plate of food.
He had known for a while that he was overweight and out of shape. But this guy? He didn't recognize himself.
"I don't have a neck, I don't have a lap ... I look like a swollen pig," said Trotter, now 42 years old. He thought: "Why hasn't someone just slapped me with something heavy and said 'You're going to die -- you look awful'? "
At first, the father of five in Wisconsin felt overwhelmed with anger and shame. He wanted his friend to take down the picture. But when he cooled off, he knew it was his own responsibility to make a change.
Trotter, the manager of payment operations for a regional health plan, had made a career of managing processes, policies and procedures. His job involved thinking about how employees could do things better and more cost effectively, based on data and measurable results.
He decided to apply those management concepts to his weight loss. He kept a journal tracking what worked for him, and by the end of three years, he had lost 158 pounds. Midway through, he began to chronicle his journey on the blog "100 small steps," and is currently trying to turn it into a book.
Here's how Trotter lost the weight:
He did tons of research. As Trotter first started his weight-loss quest, he joined a program that provided protein shakes and pre-made meals, but quickly realized "I didn't have the money or the desire to eat out of a box my entire life." He read psychological journals, fitness blogs and books about weight loss to learn the underlying causes of obesity and proven strategies that worked for other people. One book was "Fit to Lead," which looks at the connection between fitness and productivity.
He got therapy. Learning how depression and obesity may affect each other made Trotter serious about losing weight and getting help. Counseling helped him confront past disappointments, make peace with the fact that he hadn't fulfilled his dream of becoming an opera singer, and find healthier things to do when he felt stressed or upset.
"I really didn't like who I had become. I had to learn how to fall in love with that person again," he said. "I wrote down all the things I didn't like about myself and I wrote all the things I liked ... I had to learn how to like that person, and want to do things to stop abusing that person."
He kept reminders all around. That picture from New Year's Eve that made him sick? He put it up all over his house, laid a copy on the passenger seat of his car and made it the home screen on his phone. He showed the photo to anyone who would listen as a way of keeping himself accountable as he lost weight.
"I looked for opportunities to talk about it, to share my story with other people. That's my reminder all the time. That's me -- that's who I was -- and I don't ever want to go back there."
He ditched his credit card. Trotter, who spends a lot of time on the road, realized that he'd be more mindful about his food purchases if he stopped using plastic. He put himself on daily cash rations -- $10 for breakfast and lunch -- and found he was a lot more likely to buy food that was truly "fuel" instead of junk.
He turned off the TV. After a hunting trip with some buddies, it dawned on him that snow pants, boots and warm socks made it a lot more enjoyable to stay outside, even in the cold Wisconsin winter. When he got home, he took the family shopping for sweaters, warm gloves and other gear so they could spend more time outside and less time watching movie marathons and eating popcorn.
"I knew we were finally doing it right when someone asked me about a popular TV show and I had no idea what they were talking about," he wrote.
He kept workouts simple. Trotter initially was too embarrassed about his body to go to the gym, and when he did, he found his stomach was so large that it physically hurt to use the machines. But there were lots of exercises he could do at home: Stair push-ups, jumping jacks, deep knee bends, situps and other sweat-breaking routines. Now that he's thinner, he uses the gym at his office about three times a week but still does calisthenics every day at home.
He embraced routines. He only ate while sitting at the table, had a salad before each meal, and chewed each bite at least 20 times. Trotter learned another trick to curb his cravings: Brushing his teeth right afterward, when he was most likely to long for a honey bun -- his Achilles' heel.
"Trust me when I tell you, honey buns and Colgate don't mix," he said.
He didn't deprive himself. After several months of avoiding all the foods that were bad for him, Trotter said he realized he was obsessed about honey buns, cheese puffs and all the willpower-busting snacks he couldn't have. Once he allowed himself cheat days, the cravings went away. He is careful about what he eats most of the time, and in fact, he earned the nickname "Temple" because he was always talking about treating his body like a temple.
Still, he allows himself one special meal a week. He also practices restraint by putting cheese puffs in a tea cup for portion control, or eating half a candy bar and wrapping up the rest for another time.
Trotter's openness about his journey has inspired a lot of people in his life, including his boss, Tami Renz, who hired him when he was halfway through his weight loss. She herself has battled the bulge and lost 50 pounds.
"We've talked about recipes that eliminate fat, or spices that you can add that aren't salt," Renz said. "I have a tendency to beat myself up if I stepped backwards, and he says, 'It's a new day.' "
Trotter's friend Jeremy Swanson, who posted that New Year's Eve picture on Facebook, says he never thought of Trotter as obese. But he's not surprised that Trotter succeeded in his transformation.
"He's definitely faced many challenges in his life since I've known him. I've watched him own his own business and the challenge that presents ... having that many mouths to feed on a daily basis, having to pay all those bills, and he makes it happen," Swanson said. "I knew there would be results. There's no doubt that he would conquer it."
Since his initial 158-pound weight loss, Trotter says he put on about 10 pounds of muscle. Now at 6 feet tall and 238 pounds, with a 40-inch waist, he knows he still has some work to do but is much happier about how he looks and feels.
He knew he had turned a corner when he wrote in his journal a year ago: "5:15 p.m.: Really craving a honey bun ... 5:45 p.m.: Honey buns are overrated!"
He hasn't had a honey bun since.
For more of Trotter's tips, visit his blog or follow him on Facebook.
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