The 103-mile Ultra-Trail du Mont-Blanc puts even regular ultra races to shame. It's the equivalent of running four marathons up and down Mt. Everest.

By Lauren Mazzo
May 03, 2017

For many novice runners, a 5K is the end goal. For others, a half marathon is a massive accomplishment, and some strive for the marathon. Next-level runners tackle ultra races-anything longer than a marathon. These races range from 31 to 100 miles to challenge the toughest of the tough.

But even these don't hold a candle to the Ultra-Trail du Mont-Blanc (UTMB), a series of five ultra races considered the most difficult in the world. The main race logs 103 miles around Mont Blanc (the highest peak in the Alps), spans three countries (France, Italy, and Switzerland), covers more than 32K feet of elevation (equal to climbing up and down Mt. Everest), and usually calls for 20+ straight hours of running. Sound utterly unbelievable? Or at least a little insane?

Not to the 5.5K people who enter the lottery to run each year-including Amy Sproston, a 43-year-old world champ ultrarunner from Bend, OR, who is part of the Columbia Montrail Race Team. Columbia followed her during her fourth attempt at finishing the UTMB. She snagged one of the 2,300 spots to run the 2016 race, determined to finish this time. She successfully finished her first time at the UTMB-though it was a shortened course because of bad weather. The second and third time, she withdrew midrace due to health issues. And she's far from alone-usually only about half of the runners finish. (More insanity: This woman who ran 775 miles through the desert.)

Though Sproston pulled out of the 2016 race after 20 hours and 77 miles of grueling mountain terrain, she says that a race DNF (Did Not Finish) usually lights a fire under her next attempt. Shape chatted with Sproston about her ups, downs, and ultrarunning tips when it comes to tackling the toughest race in the world.

Shape: First of all, how do you train for UTMB?

Amy Sproston:I'm always racing, so I wasn't necessarily specifically training for the UTMB. I had done another 100-miler called Western States about two months prior. So, because I had just done another 100-miler, it was really about trying to recover and then get a little training in before the race. I felt pretty good after Western States and started training again within a week, then took it easy for a few weeks. When I'm training for a 100-mile race, I usually build up to 70 to 90 miles a week and try to get in some vertical, some weight training, and a little yoga too. [If you're a runner, you need to be doing this cross-training strength workout to stay strong.]

Shape: Is there anything you do to prevent injury when you're running that much?

AS: I've been running for 30+ years at this point, but I see a physical therapist once every two weeks who's always helping me work through imbalances and different issues I'm having. There's always something going on. I'll go in there feeling fine and he'll poke around and always find something that's off. I also try to get a massage and acupuncture on a somewhat regular basis as well. But this time, I was definitely a little nervous because I was having some hamstring issues and I wasn't able to run pain-free leading up to the race. So I was a little weary or hesitant going in because I knew I could potentially have some issues. The pain seems to go away after about 30 miles, so I was hoping it was going to kind of numb itself out and it would be okay, but that wasn't necessarily the case.

Shape: Just the thought of waiting30 miles for the pain to go away probably seems crazy to most people. What's your response to people who think you're crazy for running these really long races?

AS: You definitely need to break it up into pieces because if you think about going out and running 100 miles, it seems like a really far distance. But if you break it up, you know it's 6 miles to the first aid station, and you'll see your crew at mile 20, and there's another station 5 miles beyond that. So, it's really about breaking it up into little chunks. Working through it that way it seems more manageable.

Shape: What keeps you going mile after mile? Do you have a mantra?

AS: I try to remember how hard I've trained for this and all those days of getting out there and putting in the work to train. I guess that's one of my mantras; just reminding myself how hard I've worked to get here. As I get tired, I remind myself to focus on good form like hip extension and to focus on the little things that I can do to keep myself feeling good throughout the race. During an ultra, nutrition is one of the most important things, because you need to keep the calories down to have energy. Sometimes I may feel bad, but if I know that if I eat a gel within 10 minutes, I'll probably feel good again. You need to remind yourself to keep working on the little problems that will help solve the bigger problems. [That's why mentally training for a race is just as important as physically training.]

Shape: It sounds like there are a lot of issues that come up that don't necessarily have to do with the physical act of running.

AS: Most ultra runners will say that the biggest struggle is with their stomach. Last year, I really started to try to focus on getting more calories down because sometimes I'll get sick at races, and I won't want to eat at all. But you really need a calorie base to keep you going. I'm eating mainly gels and Shot Blocks, and sometimes either a mix of water or water and sports drink, but I really focus on more sugary things. [This is what you need to know about fueling for your next distance race.].

I usually have some pre-race superstitions, like eating gnocchi the night before. Otherwise, I try to eat fairly healthy and not eat a ton of fiber right before a race-something simple like rice and salmon that's kind of bland, that's kind of going to digest well. But yeah, I try to be well-hydrated and eat pretty healthy. But also know that you're going to go into a major calorie deficit, so if you want to eat gelato every day, twice a day for the three or four days before, you're going to work that off.

Shape:How did you ultimately make the decision to drop out of the race?

AS: I think it was probably a combination of being sick and having hamstring issues. I could have walked it out to the finish, but I couldn't really run at that point, and knowing that I was going to put myself further into a hole in terms of being healthy in the week following, I didn't want to push it more. In the end, I had done a pretty good job with my hamstring attachments; I did some tearing to the area and it took a few months to recover. I didn't know if it was worth it to trudge it out when I would just be doing further damage. And I want to race UTMB well, and when I was having this disaster of a race, I guess I didn't have the mental fortitude to finish it out.

I was out there for a long time, and so I definitely went through periods where I thought, "You can't quit." I guess after trudging along for so many hours, I was pretty depleted calorie-wise. Even when I started getting stuff back in, it hurt too much to try and run again. It's always a tough decision to drop; you always regret it or second-guess your decision after the fact. But I think I was at peace with what I decided to do.

Shape:How did you start running ultras in the first place?

AS: I've run since I was in junior high and I ran track and cross-country through high school and college. Then I ran a few marathons-but I had always been a very nervous racer. Before a 5K or before a track race in high school, I would often get so nervous that I would dry heave on the starting line. Even at marathons, I guess the nerves would get to me a bit. During an ultra, you have so much time to figure things out during the race. You're going to have highs and lows and issues that you can sort through. So I don't get as nervous for the longer races. I'd rather run a 100-miler than a 5K. I haven't run a 5K since my senior year in cross-country in college. They make me very nervous. Every year, I say I'm going to run a 5K and I still haven't done it yet. [Related: One Runner Tackled an Ultra In Turkey]

Shape:Do you have any advice for a wannabe ultrarunner who's nervous about it?

AS: Think of it this way: When you finish a 10K or half marathon, it's always hard to imagine going further just because you've put everything into that distance and when you finish, you want to be done. It's the same for a 50-miler or a 100-miler. After a 50-miler, it's hard to imagine the thought of going through another 50 miles, but when you go into a 100-miler, you know you're doing the full 100, so, your mind is already wrapped around that goal. It's all mental. [Ready to run? Read these pro trail running tips first.]

Shape:How do you feel about tackling UTMB again this year?

AS: For me, I've had a lot of successes and I guess I could get discouraged by how I've done at UTMB in the past, but it's also good to have a nemesis that you haven't quite figured out, and that keeps you coming back. I'm confident that some day I'll figure it out and cross the finish line with a smile.