Until 1977, professional players were not able to participate in the World Championship, and it was not until 1988 that they could play in the Winter Olympics. However, the Soviet team was populated with amateur players who were primarily full-time athletes hired as regular workers of a company (aircraft industry, food workers, tractor industry) or organization (KGB, Red Army, Soviet Air Force) that sponsored what would be presented as an after-hours social sports society hockey team for their workers in order to keep their amateur status.[15][16][17] By the 1970s, several national hockey federations, such as Canada, protested their use of the amateur status for players of Eastern Bloc teams and even withdrew from the 1972 and 1976 Winter Games.[18]