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Figure 1


Fig. 1. (A) The skates used in the present study, from the left: the bone skates, the first wooden skates with a metal blade, the skates used in the 15th and 18th century, and the modern conventional ice skates. Details can be found in the text. (B) `Winter landscape with iceskaters' 1608, a painting by Hendrick Avercamp (1585–1634). Reproduced with permission from The Rijksmuseum, Amsterdam, The Netherlands.