In this video, Roger Burlinson explains the concept of viewing descents as free speed and why, if you normally just cruise downhill, you’ll be storing up muscle fatigue for later on, when you really don’t need it.
He also compares the different types of gradient and how you need to adapt your technique to be fast whatever the terrain and argues for adopting a ‘no resistance’ approach to descents, even if you’re not interested in going as fast as you can in a challenge. It’s all about preserving your muscles and minimising the impact that negative resistance (on descents) can have on your legs.