<P> Team races are also held; in long track speed skating, the only team race at the highest level of competition is the Team pursuit, though athletics - style relay races are held at children's competitions . Relay races are also held in short track and inline competitions, but here, exchanges may take place at any time during the race, though exchanges may be banned during the last couple of laps . </P> <P> Most speed skating races are held on an oval course, but there are exceptions . Oval sizes vary; in short track speed skating, the rink must be an oval of 111.12 metres, while long track speed skating uses a similarly standardized 400 m rink . Inline skating rinks are between 125 and 400 metres, though banked tracks can only be 250 metres long . Inline skating can also be held on closed road courses between 400 and 1,000 metres, as well as open - road competitions where starting and finishing lines do not coincide . This is also a feature of outdoor marathons . </P> <P> In the Netherlands, marathon competitions may be held on natural ice on canals, and bodies of water such as lakes and rivers, but may also be held on artificially frozen 400 m tracks, with skaters circling the track 100 times, for example . </P> <P> The roots of speed skating date back over a millennium to Scandinavia, Northern Europe and the Netherlands, where the natives added bones to their shoes and used them to travel on frozen rivers, canals and lakes . In contrast to what people think, ice skating has always been an activity of joy and sports and not a matter of transport . For example, winters in the Netherlands have never been stable and cold enough to make ice skating a way of travelling or a mode of transport . This has already been described in 1194 by William Fitzstephen, who described a sport in London . </P>

When did they start wearing helmets in speed skating