and Tobogganing Federation). After it had been decided that luge would replace the sport of skeleton at the Olympic Games, the first World Championships in the sport were held in 1955 in Oslo (Norway). In 1957, the Fédération Internationale de Luge de Course (FIL, International Luge Federation) was founded. Luge events were first included in the Olympic Winter Games in 1964. Americans were slow to adopt the sport of luge. The first luge run in North America was built at Lolo Hot Springs, Montana, in 1965. Although the United States competed in every Olympic luge event from 1964 through 1976, it was not until 1979 that the United States Luge Association was founded. The first artificial American track was completed in that year for use in the 1980 XIII Winter Olympic Games at Lake Placid, New York. Since that time the United States luge program has greatly improved. A second artificial track was constructed near Park City, Utah, for the 2002 XIX Olympic Winter Games at Salt Lake City. Caitlin Nash and Natalie Corless, both of Canada, became the first all-female team to compete in a Senior World Cup doubles race in luge in 2019. Artificial tracks Artificial luge tracks have specially designed and constructed banked curves plus walled-in straights. Most tracks are artificially refrigerated, but artificial tracks without artificial cooling also exist (for example, in St. Moritz). Tracks tend to be very smooth. The athletes ride in a flat, aerodynamic position on the sled, keeping their heads low to minimize air resistance. They steer the sled mainly with their calves by applying pressure on the runners—right calf to turn left, left calf to turn right. It takes a precise mix of shifting body weight, applying pressure with calves and rolling the shoulders. There are also handles for minor adjustments. A successful luger maintains complete concentration and relaxation on the sled while travelling at high speeds. Fastest times result from following the perfect "line" down the track. Any slight error, such as brushing against the wall, costs time. Track conditions are also important. Softer ice tends to slow speeds, while harder ice tends to lead to faster times. Lugers race at speeds averaging around high banked curves while experiencing a centripetal acceleration of up to 5g. Men's Singles have their start locations near where the bobsled and skeleton competitors start at most tracks, while both the Doubles and Women's Singles