“We’re eight weeks into this and I don’t know of anyone who has missed a test yet,” WADA president John Fahey said of the new rules that came into effect on January 1.

“Surely it is best to monitor it and if there are shortfalls that emerge then we can look at it again next year. We’ve read about complaints from various people but nothing has been put to us directly,” he told a media briefing.

Under the new requirements, athletes have to inform their national anti-doping authorities of where they will be at a chosen hour between 06:00 h and 23:00 h each day for a three-month period.

If they change their plans they are obliged to inform the authorities of that change.

Athletes, who miss three doping tests over an 18-month period due to not being where they said they would be, face possible suspensions from their sport.

The new regulations have been criticised by a number of athletes groups for overly intruding into their private lives.

Several top tennis players, including Rafael Nadal, Andy Murray and Venus Williams, have argued that the rules are harder to stick to in sports where schedules are subject to sudden changes.

“There seems to be a momentum of opposition gaining over the last few days that is probably a little skewed,” said WADA director general David Howman.

“We’ve had various forms of whereabouts requirements in place for 10 years now even though some sports are just confronting it for the first time.

“I think some people are just reacting negatively to change. But it’s clear that we need out-of-competition testing because generally speaking that’s when (cheating) athletes are doping up.

“The new rules have come in after a long consultation process but we will of course continue to talk to the athletes and if there is appropriately founded criticism we will listen,” he added.

“But it makes no sense to change things already based on a few complaints in the media.”