From 340 to 174 pounds: C.B.S. man overcomes cancer, obesity while training for Tely 10

It's been two years since Glenn McMullin was an overweight man on the wrong side of 50, staring down the barrel of a deadly diagnosis.

At 340 pounds, obesity had a grip on his life and his wellbeing. His only physical fitness was the trek between the couch and the fridge.

Slowly but surely, you're feeling a little stronger. But you have to push it.- Glenn McMullin

But inside his body, there was something even worse happening — a tumour growing between his esophagus and his stomach.

It was esophageal cancer.

"It's a shock," McMullin recalls. "It takes a couple days to get your head around it and get yourself straight with what's coming up … then you get busy."

McMullin, a husband, father and airline pilot, began walking to get in shape. Slowly, he added a bit of speed to his pace.

"I was morbidly obese, so I started trying to lose some weight to get ready for the fight against the cancer," he said.

He dropped 50 pounds to gear up for the fight of his life.

'I find the good'

Then came the chemotherapy and radiation treatments targeted at an area very close to his vital organs. Doctors were unsure of how his body would bounce back from the treatment, especially after the surgery.

'You fight it off. There's always gonna be the odd grey day in there.'- Glenn McMullin

McMullin's esophagus was removed completely, along with a large portion of his stomach. A piece of stomach was stretched up to his throat to replace the esophagus.

The surgery is debilitating, McMullan said, and for more than a month, he struggled to move or eat.

But he wasn't about to let himself give up, or slip back into bad habits again.

"You fight it off," he said of the negative thoughts. "There's always gonna be the odd grey day in there, but I'm generally a positive guy so I find the good in it on the way through."

When he was able to move around again, he laced up his running shoes, this time with a different goal: to run the Tely 10.

At first, he would run 30 seconds and walk for three minutes, then run for one minute and walk for two.

Slowly, he built up his stamina until he could run continuously, and he kept going.

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"It was a little slow at first. It's a big surgery, so it takes a while to get on your feet … but every day is a little better," he said.

"Slowly but surely, you're feeling a little stronger. But you have to push it."

Running the full 16 kilometres

His short term goal was to complete the five-kilometre Terry Fox Run, which he achieved last fall.

Now his sights are set on the 90th Tely 10, a 16-kilometre race through St. John's.

On Monday morning, McMullin laced up his running shoes like he's done most days since he was diagnosed with cancer two years ago.

Despite being five weeks out of the big race, he wanted to prove to himself he was capable.

And so, at a healthy 174 pounds, he ran 16 kilometres without stopping until he returned home to his family.