Uno x / Kulset 5hour pain Cave Challenge

Magnus Kulset is a climber who races at WorldTour level, and he recently shared some really insightful thoughts on how he trains and what actually works for him.

Magnus thrives on long climbs and sustained efforts. He consistently performs best in WorldTour races with high altitude and long, demanding days. As a key domestique, he plays a crucial role in helping his team secure valuable UCI points through relentless work in the mountains.

This season, Kulset has been using a specific long-session structure only once his fitness is already very high. That’s important. The goal isn’t to build basic fitness, but to stimulate powerful adaptations without completely draining the system.

The session creates:

• Massive muscle contraction–driven calcium signaling
• Strong mitochondrial and fatigue-resistance adaptations
• High cardiovascular strain without repeated anaerobic depletion

Heart rate stays elevated for hours, energy turnover is enormous, yet the effort remains controlled enough that recovery is manageable. It’s exactly the kind of stimulus that sharpens climbing durability for long alpine stages rather than short, punchy efforts.

5 hours. Big engine work. No empty tank. FIT AND ZWO