«There are days when I just don’t want to get up, and I think maybe I won’t go today,» Waterlow said, sitting next to a pastel-coloured sofa in his modest west-side home.

«And that’s the beginning of the end really.»

Waterlow — a chatty chap with a London accent and a lanky build — will be the oldest runner to qualify for the upcoming Boston Marathon on April 20.

At his qualifying race in Oregon last fall, he came in 18 minutes faster than the required time for his age category. At Boston, there will be 15 men older than 80 taking part in the prestigious race, among a total of 30,000 marathoners.

This will be Waterlow’s third time at Boston. It’s surprising that he would return — the last time he raced there, in 2014, he fell ill mid-way through and it took him nearly six hours to finish. He was later diagnosed with acute pneumonia.

But his wife of 47 years, Karen Waterlow, isn’t surprised that he keeps on going.

«If there’s something he wants to achieve he’ll set out and achieve it,» she said.

Started running at 47

Waterlow, a former architect and emergency planner for the Vancouver School Board, didn’t start running until he was 47.

He was drinking a pint on St. Patrick’s Day in 1984 when he found out the friend he was with was training for the Vancouver marathon. Waterlow had never heard of it.

After his friend completed the race, Waterlow was impressed — and inspired. He signed up for training at the YMCA and ran his first marathon the following year.

And just like that, he was hooked. Since then, he has raced in over 100 half-marathons and 34 full marathons. Today, he trains three times a week.

«When I’m really in the zone, [I’m] not even thinking about it,» he said. «It’s like a Zen feeling.»

‘It’s a family’

Waterlow says the social aspect of running is one of the factors he enjoys the most.

«It’s a family,» he said.

Every Saturday he leads a run from a Vancouver Forerunners store. On Wednesdays, he does sprints and hill training with friends. The only runs he does alone are the long ones, every Monday.

As for his diet, Waterlow says he just eats «sensibly» — he rarely eats red meat and cut back on alcohol a few years ago after an ulcer.

But there is one food Waterlow says is his superpower: Marmite, the dark, sticky paste made from yeast that is chock-full of B-vitamins and disparaged by many.

«I’ve got about three or four jars in the cupboard right now,» he said.

‘Listen to your body’

Running has become more difficult for Waterlow, but he figures there are still a few more years in his legs.

Waterlow gets nervous before every race, and Boston is no different. With less than two months to go, he’s already fretting about what to wear.

«There’s so many things that can go wrong,» he said.

The first time he ran Boston, in 1997, he nearly got stuck in a snow storm in transit in Montreal. This time he’ll be sure to arrive a couple of days early.

But once the start gun goes off, Waterlow knows he’ll be committed, no matter what.

«That’s the moment when you can just settle down to work and listen to your body.»