Long-distance running confined area. Early tracks were usually on flattened earth or were simply marked areas of grass. The style of running tracks became refined during the 20th century: the oval running tracks were standardised to 400 metres in distance and cinder tracks were replaced by synthetic all-weather running track of asphalt and rubber from the mid-1960s onwards. It was not until the 1912 Stockholm Olympics that the standard long-distance track events of 5000 metres and 10,000 metres were introduced. Long-distance road running competitions are mainly conducted on courses of paved or tarmac roads, although major events often finish on the track
Middle-distance running uncommon in high school. Rarely run in youth competition, though some high school competitions include the 3000m steeplechase, for example, it is an event competed in championships and larger meets in New York State. Japanese secondary school boys regularly run 5000 metres on the track rather than 3000 meters. USA high school boys rarely run this distance except during cross country. Middle-distance running Middle-distance running events are track races longer than sprints, up to 3000 metres. The standard middle distances are the 800 metres, 1500 metres and mile run, although the 3000 metres may also be classified as a middle-distance