FIGURE 2.

Innovations that contributed to the progress in the development of world records over time (light blue for women, dark blue for men). Speed skating is one of many cases in which the progression of world records is driven by innovations (63). For example, the invention to improve ice quality (natural vs artificial ice) by refrigerated ovals (first 1958), spraying tiny droplets of water to smoothen the surface (first 1960), followed by the ice resurfacer “Zamboni” (Olympics 1960) and eventually indoor rinks all contributed to new records. Additionally, the development of gear such as tight-fit suits to improve aerodynamics and the invention of the clap skate that enabled a longer contact with the ice as well as further enhanced aerodynamics due to the crouched posture pushed the progress in world record development (http://www.speedskatingstats.com/index.php?file=records). Image on left was taken at the 1932 Winter Olympics and is from Henriksen & Steen (public domain, via Wikimedia Commons); image on right was originally posted to Flickr by adrian8_8.