As the grizzly bear loomed over his running partner, something clicked in Phil Troyer's mind.

"That's when I realized it wasn't a matter of chasing the bears away, it was a matter of surviving," he said.

"I was scared — but there was such a calm even in all the commotion."

It wasn't a matter of chasing the bears away, it was a matter of surviving. - Phil Troyer

He recounted the story to CBC News on Wednesday, in a voice still raw from shouting and inhaling bear spray.

Troyer encountered the grizzly and its two cubs on a trail near Grande Cache, Alta., on June 30. He was training for the Canadian Death Race with a group of runners from Grande Prairie.

The gruelling 125-kilometre ultra-marathon cuts through mountainous terrain near Grande Cache, a town about 430 km west of Edmonton.

Troyer and another runner, Lisa Lauzon, had outstripped their training group and were hiking up a rocky path used for the race when they heard shuffling in a thicket of alder bushes to their left.

Three bears attacked two runners on June 30 along this trail near Grande Cache, Alta. (Phil Troyer)

Within seconds, Troyer said he saw the distinctive brown head of a grizzly bear rise from the alders about six metres away.

He barely had time to unhook the safety lock on his can of bear spray before the animal charged.

When the grizzly was less than a metre away, Troyer fired a blast of spray at its face. The animal veered around the two runners, then circled back.

At that moment, two cubs emerged from the bushes, trapping Troyer and Lauzon between the mother and her offspring.

Troyer, who grew up hunting in the Yukon wilderness with his father, said he knew right away they had stumbled into a deadly situation.

"From there it was just chaos," he said. "Just bears coming at us. They started running around us."

In the scuffle, Lauzon was knocked off the trail onto her back. The mother grizzly lumbered toward her.

Phil Troyer's carbon hiking pole broke when he used it fight off a bear near Grande Cache, Alta. (Phil Troyer)

Troyer said he watched in horror as the mother bear advanced. The animal was growling and grunting in a way he had only heard in movies.

"I still hear that sound sometimes, and it bothers me."

His bear spray was almost empty and he doubted the stream was potent enough to deter the grizzly.

"It was the last option I had, so I just leaned over as far as I could," Troyer said.

"Everything just seemed to slow down and I remember thinking to myself, 'This has gone on long enough. What are we going to do now? How are we going to get away?"

The orange mist shot toward the bear, settling in a cloud around its face. The animal reared and turned toward Troyer, who stumbled backward onto the path.

"My pepper spray was done, there was nothing left in it," he said.

He threw aside the can and swung at the grizzly's head with his hiking pole. The carbon shaft snapped on impact, Troyer said.

By then, Lauzon had regained her feet and began throwing rocks at the bear.

"That's when the sow left, actually went up back in the woods right where it came out from."

The entire attack lasted less than two minutes, immortalized by a spike in Troyer's heart rate recorded by a monitor he wears while training.

'Be prepared, don't be naive'

Following the attack, the two cut short their 55-km run and returned to the trailhead.

Troyer said he called the leader of his trail-running group, Krista Mitchell, to relay their story.

"My heart just kept beating faster and faster," Mitchell said. "I can't imagine how he felt, because I know how I felt just listening to him."

Mitchell founded the club that was training that day, the Triple Terrain Trail Trekkers Run Group.

Each member is now required to carry at least one can of bear spray during outdoor sessions, Mitchell said.

"It was totally because of what happened to Phil," she said. "When you go out in the bush, be prepared, don't be naive and think it's not going to happen to you."

She invited Troyer to demonstrate to the club how he used the bear spray.

Phil Troyer demonstrates how to use bear spray at a meeting with his running group in Grande Prairie. (Krista Mitchell)

The workshop was eye-opening, Mitchell said. ​Many group members did not realize the can empties within 10 seconds, and must be used at close range to be effective.

"I thought it would come out more like a water hose ... not like a mist of air," Mitchell said. "I thought it would come out more hard and fierce, right in its face."

The workshop was especially useful for runners signed up for the Canadian Death Race, a two-day ultra-marathon broken into five stages Aug. 3-5.

Participants are encouraged by event organizers to carry bear spray, as long as they know how to use it.

"You are out in the mountains, there is wildlife around," assistant race manager Kelsey Cox told CBC News on Wednesday. "We really want people to be safe and to be careful."

Cox said she had heard about the recent bear encounter and said organizers would likely cancel the ultra-marathon if something similar happened shortly before or during the race.

The competition attracts endurance runners from around the world, who may have no experience sharing trails with bears or cougars.

She encouraged everyone signed up for this year's race to research risks such as bear encounters ahead of time.

"This is kind of dangerous and you are in the wilderness, and you should know what you're getting into," Cox said.

'I don't want you to be scared'

Members of Triple Terrain Trail Trekkers Run Group — including Troyer and Lauzon — will continue training on the Death Race trails near Grande Cache.

"I don't want you to stop training," Mitchell said she told her club. "I don't want you to stop going into the bush ... I don't want you to be scared. But you can't be naive. You've just got to go prepared."

Troyer said he will carry two cans of bear spray during the race.

Before challenging the 125-km course in August, he plans to revisit the path where he escaped the three grizzlies.

"I should have been dead, and I still sometimes question why I'm not," he said. "But it wasn't my time to go.

"I kind of have that peace when I go out in the woods. That if it's my time to go, I'm going to go. You just have to be prepared for that."