Become a Member

Get access to more than 30 brands, premium video, exclusive content, events, mapping, and more.

Already have an account? Sign In

Become a Member

Get access to more than 30 brands, premium video, exclusive content, events, mapping, and more.

Already have an account? Sign In



What I Learned Watching Will Bosi’s Livestream of Burden of Dreams

Will Bosi has been livestreaming his attempts on Burden of Dreams. There's a lot to talk about.

Heading out the door? Read this article on the new Outside+ app available now on iOS devices for members! Download the app.

For more than a month now, Will Bosi has been working on Burden of Dreams, a Finnish V17 first climbed by Nalle Hukkataival and contender for the most famous unrepeated boulder problem in the world.

Except Bosi didn’t actually go visit Finland (that land of fickle weather) until this week. Instead, he worked the climb at Lattice Training’s climbing facility in Chesterfield, England, logging session after session on an incredibly detailed replica of the climb, which exists courtesy of fellow UK crusher Aidan Roberts, who scanned the holds and measured the distances between them in 2021, then had the holds 3D printed and molded.

The replica was hard—harder even than the original, according to Aidan and Bosi—and Bosi spent something like a dozen sessions working its moves, even designing a pulley system to take weight off. Only after sticking all the moves individually (the replica remains a project) did Bosi decide he was ready for the real thing. And on Thursday, he livestreamed his flash attempt (!!!!) on the boulder and the first 40 minutes of his session. 

Some spoilers for those of you who didn’t watch: Bosi did not flash. However, he got dang close to doing the first move (the crux) on his first attempt. Then he rested, fell off the second move, and (apologies folks: I’ll be getting nitty gritty with the beta nerdom here) linked the second, third, and fourth moves (without the foot walk) on his second attempt. He fell on the final throw, which he promptly stuck five minutes later. After that, it was back to the first move, which he stuck on his third attempt. Then he did “the foot walk” (a tricky four-move foot sequence between the first and second move), which makes the second move far more difficult. He even finds a decent rest after the fourth move—or, rather, implements a rest that he found on the replica in the UK. 

All in all, it was a pretty baller first session (if you can call it his first) on the world’s hardest boulder problem—and, also, a pretty fascinating insight into one of the world’s best climber’s training and projecting tactics. Here, in no particular order, are my eight takeaways—which do not include the obvious one: That Will Bosi is one of the strongest climbers who’s ever lived.

1. Replica training works

Bosi is hardly the first person to experiment with replica training, but he and Aidan Roberts are, at least to my knowledge, among the first climbers to train extensively on a replica made with 3D scans. And seeing Bosi transition from the replica onto the real-life problem makes two things abundantly clear. (1) It’s very hard to get replicas right, since it’s almost impossible to perfectly mimic move size, hold texture, and steepness. (2) Despite the challenge of accuracy, replica training definitely works. There’s still beta-finding, of course, but it’s largely just a matter of adjusting to the difference between the replica and the rock. The problems are similar enough that Bosi arrived in Finland not only with problem-specific coordination and strength, but also (he says) with problem-specific skin.

2. If you’re gonna make a replica, make it hard. 

Long ago, when I still had a home wall, I used to do a bit of replica training myself, setting very rough mimicries of cruxes of my projects and then doing laps on them. My problem, however, was that I tended to make my replicas either easier or as hard as their real-world counterparts, which, though good for the confidence and not terrible for the muscle memory, wasn’t as efficient as training on a far harder replica that would make the moves on my projects feel comparatively reasonable. As Bosi himself says in his livestream: “If you want to get overly strong for this boulder, go train on that stupidly hard replica…. The first move on the replica—I know it’s an indoor move, which sucks a bit—but it’s 100% the hardest move I’ve ever done. It took me nine sessions to do it. And it was full limit even on the go I did it, when the foot stayed well and I hit the holds perfect.”

3. Having an existential breakdown every time you fall isn’t helpful

One thing that’s always impressed me about serious boulderers is their optimism. These are people who can fail on a single move dozens of times, yet instead of interpreting their present failure to do a move as indicative of a long bleak future of identical failures, they focus on the details. In Bosi’s livestream, he comes off the wall and immediately points at what he’s learned. When his foot picks on the second move, he doesn’t take his shoe off and huck it into the snow and say “I suck, I’m doomed, it’s never going to happen”—instead he laughs and examines the foothold, which is smaller and sharper than it is on the replica, and concludes that, when making serious attempts, he’ll need to wear a pair of newer shoes.

4. Speaking of shoes: Bosi sizes his very small. 

My take here may be controversial, but there’s been a lot of modern clamor about how advances in shoe technology have made the practice of radically downsizing climbing shoes archaic and unnecessary. Perhaps this is why I, an unrepentant downsizer, was vindicated to see that Bosi had to work hard to get his shoes on at the start of the session. I felt similarly vindicated when back in 2018 Adam Ondra used the same plastic bag trick I’ve relied on since it was first shown to me in 2005. And I’ll just go out and say it: I’ve tested dozens of newly released shoe models over the past year and a half, and that process has only reaffirmed that downsizing and performance go hand in hand. Sure, there’s a limit. Sure, there was a time in the late 2000s when I was probably sizing down a little too small. But I still think most people wear their shoes too big. And you know what? Will Bosi might just agree with me.

5. Is replica training our future too?

Since Hukkataival established Burden of Dreams in 2016, multiple climbers have made multiple trips halfway around the world in order to pay their dues on the boulder—a process that involves battling through conditions, skin, and sheer difficulty as they slowly hone their strength and coordination in order to make the climb feel possible. But what if, by using a replica, they could hone that strength and coordination at home, fully preparing themselves for the boulder before making just a single trip? Could that reduce both the time they must invest in these climbs and the carbon footprint associated with frequent air travel? And if the pros can do it, could mere mortals do the same thing for less heinous climbs? Could gyms start putting up nearly exact replicas of The Mandala or Jade or Midnight Lightning to help us send our projects faster? And if we sent our projects faster, would we travel any less? Or would we just acquire more projects?

6. A postmodernish question: Can you flash a problem if you’ve tried its replica?

This is a running joke in Bosi’s livestream—but, as his amazing performance on the boulder indicates, it’s also a realistic question, because it’s pretty obvious that a similarly specific training process might make V15 or even V16 boulders eminently flashable for someone like Bosi. I don’t have any answers here, but my instinct is that replicas are like chalk and kneepads and periodized training plans: tools that we ought to utilize—not try to legislate away. Maybe the better question is the opposite one, voiced in jest by Stefano Ghisolfi when he tried the Burden replica: If you send the replica is it even worth going to try the real thing?

8. Livestreaming boulders is… fun?

As a self-identifying has-been, I kind of wish that I wanted to denounce Bosi for destroying the sanctity of nature by livestreaming his projecting session. Climbing outside (my crusty self wishes he could say) is all about being disconnected, being unattached, establishing a continuity between body and world by forgetting your fans and friends and family and instead focusing all of your attention on an intricate piece of rock. But I know that’s absurd. Because one reality (and one of my own favorite parts about bouldering) is that it’s an intensely social sport. And another reality is that a single smartphone beaming a climbing session out into the world is far less impactful on the environment (and, I suspect, on the actual mechanics of Bosi’s projecting session) than a full film crew might have been. So I find myself surprisingly delighted by this development; find myself urging Bosi to livestream all his sessions, henceforth and forever. What I wasn’t delighted about, however, was a far simpler and more timeless problem: As the livestream footage makes clear, a certain someone—not calling any names because I don’t actually know who was responsible for this—made the intensely questionable decision to leave their tarps up all winter… tarps that are now lying in tatters on the ground around the boulder.

9. Someone is going to send Burden of Dreams this season

No it will not be Aidan Roberts: he’s in Switzerland, probably working on the direct exit to Alphane. No it will not be Shawn Raboutou, who, at least according to Bosi, has other plans for the spring season. And, yes, it might be Will Bosi himself.

But Bosi let slip that another contender, Toru Nakajima, who’s made three previous trips to Finland and is quite close to sending Burden of dreams, is on his way there right now. The race is on. Stay tuned.

Watch session 1:

Watch session 2:

Film: How Matt Cornell Free Soloed One of America’s Classic Hard Mixed Routes

"The Nutcracker" explores the mental challenges of solo climbing and the tactics Cornell used to help him send the route.