BRUSSELS (AP) — IOC president Jacques Rogge on Friday defended the World Anti-Doping Agency's requirement that athletes be available each day of the year for out-of-competion drug testing, despite a groundswell of protest among competitors.

"WADA has a good attitude to say that on the principle they will not budge," Rogge said. "The principle of the whereabouts is important and I believe that."

Numerous athletes and athletes' groups have complained that the system is impractical or an invasion of privacy.

Under the latest WADA code that went into effect Jan. 1, athletes must give three months' advance notice of where and when they can be located for testing one hour a day — seven days a week, between 6 a.m. and 11 p.m. The information is registered online and can be updated by e-mail or text message.

Previously, the rules applied only five days a week and athletes had to be at the stated location for only a portion of that hour.

Rogge said a spate of high-profile doping cases has turned the tables against the athletes, whether they are clean or not.

"Sports today has to pay a price for suspicion," Rogge said at the opening of an IOC-European Union liaison office in Brussels. "The best way to alleviate the suspicion is to allow for out-of-competition testing."

The 27-nation EU has already raised questions about the compatibility of the whereabouts rules with its privacy legislation. In Belgium, a group of 65 athletes has launched a court challenge against the rule.

"I understand definitely the clean athletes that see this as an invasion of privacy," Rogge said.

Although the principle cannot be changed, he said "the circumstances could be adapted" through consultations between WADA and athletes.

Rogge said efficient out-of-competition testing is a cornerstone of anti-doping controls. To catch cheats, short-notice tests are essential since many illegal substances can become untraceable within 24 hours.

"Without whereabouts you cannot have out-of-competition testing," Rogge said.

Top-ranked tennis stars Rafael Nadal and Serena Williams and FIFA have all criticized the current rules as overly invasive.

WADA director general David Howman met with athletes' groups in London earlier this week to hear their concerns.

Howman said WADA would stick with the rule but would consider any legitimate changes later if serious problems emerge.

"It's only been in place for six weeks," he said. "It needs to develop and we'll see how it runs. If there are hiccups or problems in the system, then we will be receptive to suggested changes. We've got to give these things a try."