Lori Barclay just wants to fly on a plane without needing a seat extender or seeing the horrified look from a passenger faced with sharing a row with an obese woman.

She wants to go to an amusement park without dreading the attendant telling her she’s too big for the ride.

She wants to shop at the mall without someone having to fetch the car and pick her up at the other end, because she’s in too much pain to walk back.

“Most importantly, I would like to play with, get on the floor with, and chase my four grandchildren,” she says. “I just want to live my life again instead of just existing.”

Barclay, 47, declared 2012 as the year she reclaims her health. She signed up for her first 5K. She plans to walk the Kaiser Permanente Corporate Run/Walk in September.

She took action right away. She joined Weight Watchers and hired a personal trainer. She is taking Zumba classes, something she never dreamed she would do.

She vowed to chronicle her journey on Facebook so family and friends could track her progress and also to keep herself accountable.

Severely overweight since 2004, Barclay is motivated. Her goal is to lose 100 pounds in one year and eventually lose 125 pounds. She also wants to lose inches and lower her blood pressure and cholesterol.

For now, she is staying off the scale and measuring her progress in inches. She has lost four inches from her waist.

Motivation is what powers a first-time participant through the training phase and to the starting line of the 5K.

“Consistency is the most important part of conditioning and fitness,” says Jeff Galloway, an Olympian and running expert who has directed the Kaiser-Permanente Corporate Run/Walk for 30 years. “Motivation is the most important factor in staying consistent.”

Barclay was motivated to get healthy by a friend who died recently. The friend, who was the same age as Barclay, changed her unhealthy lifestyle, but the excess weight and years of smoking had already taken their toll. “I can’t wait until it’s too late,” Barclay says.

She will have plenty of company as she walks the hilly 5K course. Many of her colleagues at Northwestern Benefit Corporation of Georgia are participating. Her personal trainer is planning to walk with her, as is the assistant manager at Just Fitness, the Alpharetta gym she drives 30 minutes each way to for her workouts. Her boyfriend, Barry, will be by her side, as will her best friend, Christine. A high school friend she hasn’t seen in years might drive over from Alabama to join Barclay in her quest.

“I’m excited to see how far I can really push myself to succeed,” Barclay says. “If I can make it to the end of this walk, I know I can do anything I set my mind to.”

About this series: Training for Your First 5K appears Wednesdays and features expert advice for all aspects of preparing for a 5K. Created by the Kaiser Permanente Run/Walk & Fitness Program, the goals are to inspire metro Atlantans to get fit and to promote workplace wellness.