Preprint / Version 1

The kinematic changes following a training intervention on pumping in slalom


  • Christian Magelssen Department of Physical Performance, Norwegian School of Sport Sciences
  • Robert Reid Norwegian ski federation
  • Live Steinnes Luteberget Department of Physical Performance, Norwegian School of Sport Sciences
  • Matthias Gilgien Department of Physical Performance, Norwegian School of Sport Sciences
  • Petter Andre Husevåg Jølstad Department of Physical Performance, Norwegian School of Sport Sciences
  • Per Haugen Department of Physical Performance, Norwegian School of Sport Sciences



Motor learning, Generalized Additive Model, Alpine skiing, Skiing technique, Pumping to increase velocity


Slalom racers rely on effective strategies to bring them down the course in the shortest amount of time possible. One proposed strategy that skiers can use to achieve this goal is to pump themselves to higher velocities by extending their center of mass closer to the turn's axis of rotation from a laterally tilted position during the turn. However, the effectiveness of this proposed strategy and its potential magnitude are much debated. In a previous study, we found that skilled skiers (n=66) greatly improved their race times after training to pump on flats in slalom. Here, we ran a follow-up study and explored the kinematic changes that may explain this improvement in a smaller sample (n=18) of this larger pool of skiers, where we recorded the positions of the skiers using a local positioning system in the upper section of the course. Using a Bayesian estimation approach, we found that the speed profile of the skiers changed greatly, with a change pattern consistent with what we would expect from pumping. We also found a general trend that the skiers had a longer path length at retention, though the change was less consistent from gate to gate. Pumping to increase speed on flats thus appears to be an important strategy for increasing speed on flats.


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