
9A Mastery: How Will Bosi is Redefining Elite Bouldering
About this episode
In this special episode of the Lattice Training Podcast, host Tom Randall sits down with elite climber Will Bosi to discuss his remarkable second ascent of Spots of Time (9A/V17) on Helvellyn. Will offers a deep dive into the physical and mental challenges behind his historic climb, sharing the preparation, training strategies, and mindset that helped him send one of the toughest boulders in the world.
Will reveals how he adapted the original sequence for his own climbing style and collaborated with fellow climber Aidan Roberts on beta, making this achievement a true test of both physical endurance and climbing intellect. They also explore Will’s unique approach to training—mimicking moves from the ground to conserve energy and protect skin—and how this method helped him succeed.
In addition, the discussion touches on grading comparisons between other legendary climbs, including Burden of Dreams and Alphane, and Will’s thoughts on pushing the limits of elite bouldering. Will also shares insights on his new chalk brand, Bosi Blizzard, crafted to tackle tough conditions and support endurance on the sharpest holds.
With insights into the mental toughness needed to handle the pressure at the top, and a sneak peek into his future projects, this episode is a must-listen for climbers aiming to understand the mindset behind high-level ascents.
Key Takeaways:
- Will Bosi's adaptation of beta and sequence for Spots of Time
- Unique training methods to conserve energy and protect skin while preparing for a major project
- The mental preparation required for tackling world-class bouldering challenges
- How Will’s Spots of Time send compares to other 9As he’s tackled
- The evolution of climbing grades, including potential V18 projects
- What’s next on Will’s radar, from Japan’s hardest boulders to new UK projects
Tune in now for this exciting discussion on breaking boundaries in the climbing world!
And for Bosi Blizzard checkout https://williambosi.com/
The Lattice jingle is brought to you by Devin Dabney, music producer of the outdoor industry who also hosts the American Climbing Project.
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