(L-R) Julia Kern, Jessie Diggins, Alayna Sonnesyn and Lina Sutro of the SMS T2 Team inside the training tunnel on Aug. 28 in Oberhof, Germany.
When 10-time Paralympic medalist Oksana Masters casually dropped the phrase “underground snow tunnel” in a Zoom call with a group of journalists, the response she was met with was, huh?
“It’s exactly what it sounds like,” the cross-country skier said about the tunnel camp she had just finished in Oberhof, Germany. “It’s underground, and it’s snow they keep all year-round that they can man-make or preserve from the previous winters.”
While there is a smattering of tunnels throughout Europe, the world’s first cross-country ski tunnel was created in Vuokatti, Finland, in 1998 and was built into a mountain. Germany and Sweden are home to the other two big snow tunnels, with the latter being an old military facility inside a mountain converted in 2006.
The benefits of ski tunnels are numerous, but at the top of the list is being able to get on snow well before it gets cold outside — some of the tunnels open as early as June — as well as being able to control the temperatures and conditions inside them.
Of course, the downside is “it isn’t as beautiful as skiing in the mountains,” explained Masters. And since “it’s cement walls, it means no room for error if you do miss the turn.”
Her teammate — two-time Paralympian and three-time gold medalist — Kendall Gretsch — has been utilizing “tunnel camps” with Team USA since the fall of 2017, just ahead of her first winter Games. The 29-year-old said the tunnel camps usually last around 10 days, and the team tends to do them once a season.
“With the exception of last year [due to the pandemic], we’ve done a tunnel camp every year,” the para triathlete, biathlete and cross-country skier said.
“Because it’s a tunnel, it’s not that large. So, in Oberhof, there is a one-kilometer loop and then small branches that go off that, so there’s not a lot of snow you’re working with,” she said.
Sessions tend to last an hour and a half to two and a half hours — depending on how many they do in one day. “If you were there for two and a half hours, you could get in a lot of loops,” said the skier who took two golds in the Paralympic Games PyeongChang 2018 — the 6K biathlon and 12K cross-country.
After a couple of days in the tunnels, the team will usually “go walk around town and be outside — because otherwise, you’re inside a lot,” she said.
Thankfully there are windows in the tunnels, “so you can see outside,” fellow Team USA skier Julia Kern said. “And every week, they actually open the doors and essentially replace the air and reset the track.”
After seven years on the U.S. ski team, Kern got her first experience with the tunnels this past summer.
“I mentally prepared myself for this out and back little strip of snow, but I was pleasantly surprised that there were a few hills and varied terrain,” said the 24-year-old about her time in Oberhof, which features 10,000 square meters of skiable snow.
With her first race of the season fast approaching, she admitted it was difficult to prepare when they still don’t have any snow where she trains in Vermont. “Obviously, since our sport is skiing on snow, that’s the preferred method to train.”
In the offseason, her preferred training method is rollerskiing because “getting on snow in the summer often has a higher cost than staying home and rollerskiing,” she said. “It’s a good alternative, but I would prefer to be on snow.”
Gretsch couldn’t agree more. “You can do cross-training or time on an erg, but the feel of being on snow is just really different,” said the dual-sport athlete who took gold in the Paralympic Games Tokyo 2020 in paratriathlon.
Another benefit to the tunnels and their well-kept trails is that it gives you the ability to test out equipment before you are competing in them. “You see a lot of people testing skis in the tunnels,” Gretsch said. “We’ll go over to Europe and pick out skis for the season, and then you can go into the tunnel and see how they feel on snow.”
The conditions inside the tunnels don’t vary, Kerns shared, but the same can’t be said for the snow on the mountain.
Thanks to global warming, ski conditions are constantly changing from one season to the next.
“We had a world cup a couple of years ago where they had to significantly change the course because they didn’t have enough snow, so we’re definitely seeing more manmade snow and having to rely on it,” Gretsch said.
It’s not just the U.S. national team that takes advantage of the tunnels. “When we were in Oberhof, the Swiss biathlon team was there, Germany obviously had several people there, Russia was there for a bit, and then the Para Great Britain Nordic team was there as well,” Gretsch said. “The morning is set aside specifically for training, and the afternoon is more club groups.”
Outside of that ski world, “tunnel camp” is not a known phrase. “It’s hard to explain,” Gretsch said. “If you don’t see it, it’s hard to picture what it looks like. I say it’s like a refrigerator tunnel or a refrigerated parking garage.”
Whatever you call it, it’s one innovative way Team USA is maximizing their training with their sights set on Beijing 2022.