Denise McHale is a threat in any race she enters, regardless of distance or the competition, man or woman.

This weekend will mark McHale's third year competing in the Yukon River Trail Marathon, which is set to start from Shipyards Park on Sunday.

The Full Marathon and the Half Marathon walkers will both start at 8:30 a.m. The Relay will begin at 9:15 a.m. and the Half Marathon will go at 10 a.m.

McHale – who regularly represents Canada at International Association of Ultra Runners (IAU) events – is entered in the Full Marathon.

The Whitehorse runner took first overall in the 2009 river marathon and second overall (top female) in 2003, when she broke the women's record.

In July, she finished 10th overall with a time of eight hours, 48 minutes and 35 seconds over 70 km in the IAU World Trail Championships in Connemara, Ireland.

Adjusting her strategy from the ultra to full marathon is simple: run faster, she says.

"The pain is a little bit more intense but over a shorter time. For me, it's a good training race, a good chance to get a really hard run in.”

McHale and her husband Greg are preparing to run 193 kilometres in the open mixed category of the 2011 Gore-Tex TransRockies Run in Colorado from Aug. 21-26.

In addition to competing, McHale sits on the organizing committee of the Yukon River Trail Marathon, which on Tuesday topped out with roughly 300 competitors for the third year running.

This year's field will feature 53 runners in the full marathon, 86 in the half, 157 in the two-four person relay and eight half marathon walkers, a new division added this year.

Of the competitors, 27 are from outside Canada.

There are 22 Americans entered – the majority of which are Alaskans, though runners also hail from Idaho, Illinois and California – three Germans and two Spaniards.

In previous river marathons, runners came from as far away Japan and Australia to test their meddle in the Yukon.

Board member Keith Thaxter said the river marathon's increased popularity in recent years can be attributed to a number of factors.

Near the top of the list is the media attention the event has received.

In 2010, Canadian Running magazine voted the Yukon River Trail Marathon one of Canada's top 10 must-do trail races.

The quality of the race has attracted that kind of attention, and that kind of attention can only up the profile of the event, Thaxter said.

"They looked all over Canada, and they identified it as one of the most nicely laid out, scenic trails, and it was therefore suggested it is something an avid marathoner or trail runner should experience.”

"It is a very beautiful, scenic course as you run along the riverbend and up in the canyons, a lot of nice scenery that you don't get elsewhere.”

Evidence: the international flavour the river marathon draws each year.

"You will find that there are people who are touring around, and it's one of the things, there are people who are avid runners, bikers, hikers, canoers, they're always looking for what's going on in the area, and they'll make a point to be here for a particular event,” Thaxter said.

"And then if you've got positive press, for things like being noted as a good marathon, people are going to say, ‘Wow, I should go up there for that, because I want to go see the Yukon, but also, I want to take that event in.'”

McHale agreed.

"A lot of runners look for destination marathons, a nice place to go and go do a race,” she said.

"It's a great course, it's very scenic, it's got a nice grassroots feel to it. I think it's great they got the relay division as well; it's a great way to get people involved.”

Thaxter was just one of the Yukoners to finish near the top of the heap in last year's event: fourth in the full marathon with a time of 3:38:49.

Fellow Yukoner Michael Richards won the full marathon in 3:13:37, while Whitehorse's Rodney Hulstein won the half marathon in 1:19:32 and Teslin's Karl Blattmann took second (1:24:51).

There's no question of home-court advantage, Thaxter said.

A dedicated marathoner, Thaxter said the river marathon is one of the toughest he's attempted.

"This course is really challenging. I've run in a lot of marathons, and I would say out of the trail marathons, it's probably one of the most challenging.

"You really feel beat up, so it's really a challenge to pace yourself.”

The edge for the local competitors is knowing the terrain.

The Sportslife Thursday Night Trail Run has lately been using portions of the course.

That weekly experience gives local runners a clear picture of what to expect come race day, Thaxter pointed out.

"Knowing the course is a key advantage with any marathon, but everyone here who's running locally has run this many times and knows the advantage of pacing themselves, where the hills are and where the downhills are, when to relax and when to turn it on,” Thaxter said.

The second major factor in the increased popularity of the river marathon is the increased popularity of running itself in the Yukon.

The half marathon walkers were included because the interest was there, he added.

"It allows them to be a part of the event, that's basically what you're doing. And maybe some of them by preference will walk or they just aren't runners, or for physical reasons choose power walking versus running. It just adds to the event.”

Thaxter credited the City of Whitehorse, and trail planner Jane Koepke, with helping revitalize the sport.

"In general, the local running community is growing, it seems. There's a lot of people coming out for the Thursday trail runs.

"And this particular course is run during the trail running season, and also all the work that the city has done with their trail improvements,” Thaxter said.

In the future, Thaxter said organizers may look into increasing the number of registrants to accommodate the growing numbers.

"It just has to do with logistics of getting everything prepared for the volunteers and for the runners and the jerseys, all the things you need to buy in advance. You can't really leave it wide open, otherwise you'll be without.”