For example, there’s “Félix Erausquín”, who invented a javelin throwing technique you probably never heard of.
http://rethinkingathletics.blogspot.com/2013/12/the-javelin-...:
However the true revolution of javelin throw came in 1956 when a 49 year old spaniard, Félix Erausquín, invented what came to be called the “spanish style”. Erausquín was a specialist of shot put and discus throw (with several national titles and records) but also of the “barra vasca” which consists in throwing a heavy rod using a rotational technique. Erausquín adapted the style of the barra to javelin throw with a greased hand and managed a throw of 83.40 m at a few centimetres of the world record.
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Could the spaniards have won the 1956 Olympic javelin title? Yes and no. Had they kept the style secret till Melbourne they would certainly have taken the javelin world by surprise. However at the beginning of October, a month and a half before the Games, Salcedo used the new style during a competition in Paris. This opened the way for experimentation with the new technique to non-spanish athletes but also alerted the instances of the international federation who by the end of the month had modified the rules so as to ban the rotational technique. However, even if they had kept the secret, the athletes from Spain would not have had the occasion to throw at Melbourne since Franco’s government had, at the last moment, decided to boycott the Games.