It was the first-ever 5K race for Smith, then 41 years old, who had been running for three months and had gone 148 days without a cigarette.
Surely, she thought, the finish line must be right ahead.
"I come around the corner to see 3K and I thought, 'Oh man. Two more to go and I think I'm gonna die,'" recalled Smith of that day last spring.
"But when I came around the next turn, there was my mom, my mom's boyfriend, Tom, and my little nephew. They were all there cheering me on and Tom yelled, 'What are you running for?'
"It was a couple of things," Smith continued. "I didn't think I could do it. I didn't think anyone thought I could do it."
For the final two kilometres, Smith set out to prove herself and everyone else wrong. The Halifax woman distanced herself from her former life as a smoker with every stride until she reached the finish line where her grown daughter was waiting.
"It was just joy rising," said Smith. "I started to cry."
It was an achievement she didn't think was possible before joining the Lung Association of Nova Scotia's Learn to Run for Smokers program a few months before.
The eight-week training program, launched in 2009 and believed to be the first of its kind in Canada, teaches current and former smokers to kick the habit for good and pound the pavement. It is offered throughout Nova Scotia and was introduced in Alberta last year.
Robert MacDonald, the association's manager of health initiatives, said the secret to success is building self-esteem in smokers who've already tried everything else.
If a smoker can learn to run, jog or walk five kilometres by the end of the program, maybe ditching cigarettes isn't so far-fetched, he said.
"We're not trying to create marathon runners here," said MacDonald. "We're building confidence in these people to know they can achieve goals."
It's a subtle approach that involves making addictions experts available, but avoids lecturing participants on the dangers of lighting up.
"Smokers know it's not good for them," added MacDonald. "We're not there wagging our finger saying, 'You shouldn't be smoking.'"
Smith had her first cigarette at 13 years old. She tried countless times to quit, but only succeeded while she was pregnant.
Soon she was back to smoking two or three packs a week and struggling to get rid of post-baby pounds. In April 2011, she was diagnosed with asthma.
"I'd go up just a flight of stairs in my house and be winded," she said. "It was just like, 'Wow, what am I doing?' Before it didn't seem like (smoking) was affecting my health."
Later that year, Smith signed up for lessons with a personal trainer and eventually lost 35 pounds. On Christmas Eve, she smoke her last cigarette. Several months and excuses later, she joined the Lung Association's program.
Jamie Fraser, a community outreach worker in addiction services with Nova Scotia's Guysborough Antigonish Strait Health Authority, said relapse is a common problem. Most smokers will try six or seven times before successfully kicking the habit.
"People will refer to a cigarette as a friend and a companion," he said. "We try to get people to realize it's a toxic relationship, a very one-sided relationship. (It's) killing them and costing them a fortune."
Fraser said combining efforts to quit with other healthy choices makes it easier to butt out permanently.
"As they succeed in the activity, the smoking will drop off," he said. "It doesn't fit with that lifestyle."
Smith plans to train for the next Blue Nose 5K when the Lung Association program starts again this week in the Halifax suburb of Dartmouth.
She has a personal time to beat, though she feels she's already won the battle over cigarettes.
"When you start putting some positive things in, you almost can't help but keep going," she said. "And smoking is probably one of the worst things you do to yourself."
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