Ski Science #1: How Many Phases Does a Ski Turn Really Have?
How Many Phases Does a Ski Turn Really Have? A Cross-Country Comparison — and Why Steepness Changes the Answer PowerSki Lab | Ski Technique · Biomechanics — By Dr. Sungchul Yang Introduction Ask any certified ski instructor how a turn is structured, and you'll likely hear some version of "initiation, control, finish, transition." It's a clean, teachable model — but is it universal? Does a racer on a steep giant slalom pitch experience the same turn structure as a recreational skier cruising a groomer? In this post, we dig into ski instruction manuals from North America and Japan, alongside peer-reviewed alpine ski racing biomechanics research, to answer both questions. 1. Turn-Phase Models Differ by Country — and by Purpose In the United States (PSIA) and Canada (CSIA), a rough three-part logic — initiation, shaping/control, finish — shows up repeatedly, but there is no single fixed, universally adopted standard. The terminology has actually shifted over time: an ...