“…Therefore, a biomechanical understanding of changes in techni-30 que during learning can provide objective, quantitative information which is useful for assessing and enhancing the process of skill learning. Previous research has investigated the mechanical energy exchanges during gross motor skills such as 35 the pole-vault (Schade, Arampatzis, & Brüggemann, 2000), sprint running (Bezodis, Kerwin, & Salo, 2008) and gymnastics high bar skills (Arampatzis & Brüggemann, 1999, 2001Irwin & Kerwin, 2007;Okamoto, Sakurai, Ikegami, & Yabe, 1987). 40 However, changes in mechanical efficiency during learning have more often been examined for laboratory based tasks such as crawling (Sparrow & Irizarry-Lopez, 1987) and reaching movements (Schneider, Zernicke, Schmidt, & Hart, 1989), for 45 which efficiency improves with practice.…”