When I first started mountaineering it became clear to me that there were two things I needed to be successful. And no, I'm not talking about a lighter ice axe or more breathable clothing.
Nope. What I need were legs and lungs.
I realized that I needed to be able to walk uphill forever. And I realized that I needed to be able to breathe while I walked uphill forever.
The problem is that nobody can really walk uphill forever. Going up into the sky on a snowy peak really works the quads. Tired quads, plus walking uphill early in the morning, plus altitude, equals tired lungs.
There is a simplistic trick that can help you to preserve both your legs and your lungs. The Mountaineer's Rest Step is a technique that slows you down a bit -- which helps you keep your breath -- and allows you a micro-rest on every step. In the simplest terms, all that you have to do is lock your knee on every step. Locking your knee allows your body to rest on your skeletal system instead of on your muscles.
The Rest Step definitely slows you down. Some might say that this is far from ideal when trying to cover a lot of ground, but the reality is that slow and steady wins the race. It's always better to go slower and take less breaks than to go fast and have to stop a lot.
The Rest Step is a key mountaineering technique. On long summit days it doesn't get any better than taking a mini-rest with every step.