Olympiad beginning on the opening of the Olympic Games for the summer sports. The first modern Olympiad began in 1896, the second in 1900, and so on (the 31st began in 2016: see the Olympic Charter). The ancient and modern Olympiads would have synchronised had there been a year zero between the Olympiad of 4 BC and the one of 4 AD. But as the Gregorian calendar goes directly from 1 BC to 1 AD, the ancient Olympic cycle now lags the modern cycle by one year. An ancient Olympiad was a period of four years grouped together, counting inclusively as
Chess Olympiad the Olympiad. The tests were first introduced in 2002 under significant controversy, with the widespread belief that it was impossible to dope in chess. Research carried out by the Dutch chess federation failed to find a single performance-enhancing substance for chess. According to Dr Helmut Pfleger, who has been conducting experiments in the field for around twenty years, "Both mentally stimulating and mentally calming medication have too many negative side effects". Players such as Artur Yusupov, Jan Timman and Robert Hübner either refused to play for their national team or to participate in events such as the Chess Olympiad where