When Glen Plake tells you to wear a costume, you don’t say no.

For nearly three decades, the 51-year-old freeski legend has been a fixture at the SnowSports Industries America Snow Show, held this weekend in Denver. It’s one of the few times you’ll find him in sneakers instead of boots and skis, although he still wouldn’t be caught dead without his signature mohawk. The guy just knows how to wow the masses.

He also knows how to make a lung-busting race way more enjoyable than it should be. Three years ago, SIA linked up with Copper Mountain and the Cosmic Ski Mountaineering Cup to launch a beginner-friendly skimo race in conjunction with the resort’s on-snow demo day. It’s a fun-loving event built around beer and benefits — the tagline is “the weak, strong and the thirsty” — with all proceeds going to the Colorado Avalanche Information Center.

But it was still missing something. And then Plake suggested costumes.

“Costumes are recommended and encouraged and pretty much mandatory,” said Joe Risi, founder of the winter-long Cosmic series, who says the whole costume concept was Plake’s idea. “You’ll actually be fined a time penalty if you don’t wear a costume.”

Needless to say, the mohawk’s suggestion is now part and parcel of the Uphill/Downhill Challenge. The race returns to Copper on Feb. 1 with two events: an industry-only race with one uphill leg and one downhill leg, and a public Cosmic series race with two legs of each. Both require teams of three, costumes, avalanche gear and, of course, a healthy sense of humor. (Online registration is open until noon on race day.)

The concept might be lighthearted, but the competition promises to be as steep as always. Risi expects Plake to race with an unnamed team, and 2015 industry winner Eric Henderson returns to defend his title.

“We really try to make this a fun and festive environment, hence the costumes, the funny names, everything else we have,” said Henderson, known as Hende to friends and foes on the course. “It all plays into this concept that it’s not about winning — it’s about having a good time.”

A taste of skimo

The course will be familiar to past competitors, Risi said. Beginning at noon, skiers in both events leave the start line at Center Village and skin up Main Vein (just east of the America Eagle line) for about a quarter-mile. The course then turns into the trees for a stretch of skinning and kick turns in the thick stuff before returning to a gladed run for the downhill stretch.

Here, SIA racers continue through the glade to the final stretch, while Cosmic racers turn around and head back uphill for more switchbacks and kick turns in the trees. The industry race is about 800 vertical feet of climbing and the other is about 1,100. It’s pretty mellow for a Cosmic race, Risi admits, but it still stays true to the mountaineering roots of the 32-event series.

“We’re not just going up a run and then back down a groomer,” Risi said of the series, which tends to attract high-level skimo athletes. “This is a true glimpse at what ski mountaineering actually is.”

After cruising downhill through the glades, competitors in both races ski through slalom gates and then a mini terrain park with jumps and rollers. The final stretch is a boot sprint: everyone must unclip and run through Burning Stones Plaza to the finish line, skis in hand.

“There are a lot (of races) in the U.S. that act as two things: one as an intro to the sport, the other as a true, competitive uphill event for elite endurance athletes,” Henderson said. “The beauty of the SIA race is that I see it as a gateway drug for uphill racing and skiing.”

Henderson is no stranger to skimo racing. The Boulder native competed in all four Rando Rise and Shine races at Arapahoe Basin this season and has tackled the Grand Traverse in the past. The Uphill/Downhill Challenge is in an entirely different class, but he still enjoys it for the unadulterated energy of a costumed crowd. And, of course, the downhill.

“I love that you get to ski downhill once you get to the top,” Henderson laughed. “It’s a way to integrate one of my favorite sports, which is downhill skiing, with that adrenaline you get from pushing uphill. It’s the best mix of exercise and pure fun.”

Last year, Henderson and the winning Colorado Edibles crew with Dynafit hit the course in their beachfront best: Hawaiian shirts, Bermuda shorts and Ray Bans. Now he’s with Backbone Media, but he’s just as confident the team will finish at the top of the industry pack. Their costumes for this year?

“Oh, it’s decided,” Henderson said, “But I can’t give anything away. You’ll just have to come out and see it in person.”

Plake would be proud.