A shock weekend is a training method that simulates the conditions of an ultratrail race in terms of accumulated time on feet, elevation gain, and more. The concept can also be applied to building durability for road ultras. A shock weekend typically involves several hours of endurance training (4-12, depending on the goal race) each day, spread over two to three consecutive days.
Guillaume Millet coined the term and developed the method. I first came across it in his book “How to Succeed at UTMB®” (the English version has been out of print for some time).
