Olympian Jessie Diggins explains why cross-country skiers aren't just "little forest fairies in spandex"

• Cross-country skiing might seem easy, since it's a sport anyone can pick up.
• But at the Olympic level, it's a brutally exhausting event.
• US Olympian Jessie Diggins, who's competing at the Winter Olympics, spoke to INSIDER about the sport.
• "It's really aggressive because, unlike track or swimming, you don't have to stay in your own lane," she said.

For an average person, cross-country skiing is a pleasant way to spend a winter afternoon. For an Olympian, cross-country skiing is a punishing test of strength and endurance.

But American skier Jessie Diggins - who's currently competing in Pyeongchang 2018 - promises that it's fun, too.

"People used to see us [as] these little forest fairies in spandex, and we go up into the woods and come back two hours later and that was the race. It's so much more dynamic than people realize," Diggins told INSIDER in an interview before the start of the Winter Games.

"It takes everything you have to get around that course, because you're working your legs, your arms, your core," she added. "The way I'm describing it, it sounds like it couldn't possibly be fun because it's so hard. But it actually is fun."

Of all Olympic sports, cross-country skiing is known as one of the most exhausting. At the Winter Games, there are seven cross-country events ranging from 1.5 to 50 kilometers in distance.

Pro skiers also move at a grueling pace that torches calories. According to data from the Compendium of Physical Activities - a research-backed list of how many calories are burned by different activities - a 200-pound elite skier would burn about 1,300 calories in an hour.

Given that level of exertion, it makes sense that many skiers collapse the moment they finish a race.

"You see people cross the finish line, it's just like rag dolls flopping everywhere. That's a pretty typical scene for a cross-country ski race," American skier Andy Newell once told NBC Sports.

Diggins said that in the short sprinting events, skiers get tangled in crashes and pile-ups, too.

"[In] sprinting you're going head to head, people are breaking poles, they're crashing," she said. "It's really aggressive because, unlike track or swimming, you don't have to stay in your own lane. It really shakes things up."

Diggins made her debut at the Sochi Games in 2014 and, in the lead-up to the 2018 games, she partnered with Ice Breakers and several other US athletes for "Team Unicorn" - a campaign celebrating Olympians' inner confidence.

She went into the Pyeongchang Games hoping to end a US medal drought. It's been 42 years since the last American man won a medal in cross-country skiing, and no American woman has ever medaled in the sport, according to NBC.

So far, Diggins has fallen short of that goal. She placed fifth and sixth in the ladies' skiathlon and sprint events, respectively. But she has another shot at the podium on Thursday, February 15, in the women's 10-kilometer event.

"I'm coming into [the 2018 Olympics] with so much more experience and a couple more thousands of hours of training under my belt," she said. "In every way, I am not the same skier I was in Sochi and I have a lot more confidence in myself."

There's still time to catch the cross-country skiing action the Pyeongchang Olympics. Check out the full schedule here.

Want more? Read all of our coverage of the Winter Olympics here.

Sign up here to get INSIDER's favorite stories straight to your inbox.