London: The International Olympic Committee dispatched details of the tough anti-doping regulations it will implement at this year's Beijing Games to all national committees on Thursday.

Under the new rules, the IOC has increased the number of tests from the 3,600 conducted in Athens four years ago to 4,500 as it pushes for a cleaner Olympics.

Other elements included in the revised regulations for the August 8-24 Games are that athletes can be tested more than once on the same day and even the possession of a prohibited substance will constitute a violation of the rules.

Doping tests

The IOC will take charge of delegating doping controls from July 27 when the period of the Olympic Games officially starts. Until that day, doping controls will be the responsibility of World Anti-Doping Agency.

There will be a total of 41 doping control stations, 34 in Beijing and seven in the co-host cities where some other sports will be staged.

"The samples will be analysed in a period of between 24 and 72 hours only, depending on the kind of test," the IOC said.

Patrick Schamasch, the IOC's medical director said preparations for doping controls were on track in Beijing.

"Everything is going very well and the collaboration with our Chinese colleagues is excellent," Schamasch told Reuters in London on Thursday,

"Preparations are perfect," he added.