Bryan Fish is the former CXC Team Vertical Limit head coach, and now coaches for the U.S. Ski Team. FasterSkier approached Fish about CXC’s unique approach to periodicity–the sequencing of hard and easy blocks in a training plan–and this was his response. We got an e-mail from a reader with a story idea—he mentioned that CXC takes a different approach to periodicity, alternating hard weeks with easy weeks rather than doing the typical three-week progression....