Jacques Rogge, who became president of the International Olympic Committee in 2001, when the organization was still reeling from an ethics scandal, and helped restore stability during his 12 years in charge while taking a strong stand against doping, has died. He was 79.

The committee announced his death in a statement on Sunday. It did not say where he died or specify the date or cause, though Dr. Rogge had been in declining health.

Dr. Rogge was an Olympian himself, having competed for Belgium in sailing at the 1968, 1972 and 1976 Games. He was also a skilled rugby player when younger and was a member of the Belgian national team.

He was an orthopedic surgeon, a practice he gave up when he took the Olympic post, and his medical background informed his stance against doping, a problem that continues to vex the Games and sports in general.

Dr. Rogge greatly expanded the testing of athletes, advocated longer bans for those who test positive and sought cooperation from the pharmaceutical industry in the search for cheaters.

“The No. 1 issue is doping and everything we have to do to reduce this evil,” he told The New York Times a year into his presidency. But a decade later, as he was preparing the leave office, he acknowledged that the issue had become more complex than ever.

“Sophisticated doping often implicates organized crime networks, which operate beyond national borders,” he told The Associated Press in 2012. “We need help from governments, but also those who are there to apply the law, scientists, the medical community, coaches and the pharmaceutical industry.”

He also pushed to establish the Youth Olympic Games, which began in 2010 and focus on teenage athletes.

“He will be remembered particularly for championing youth sport,” Thomas Bach, the current IOC president, said in a statement, “and for inaugurating the Youth Olympic Games. He was also a fierce proponent of clean sport and fought tirelessly against the evils of doping.”

Jacques Jean Marie Rogge was born on May 2, 1942, in Ghent, Belgium, to Charles and Suzanne Rogge. His father was an engineer, and his mother was a homemaker. He learned from his father the sailing skills that would later take him to the Olympics.

“My father sailed, and kids do what their father does,” he told The Times in 2001.

His father also played hockey and pressed his son to take it up.

“I was fit and fast, but had no technique, so I stayed with sailing,” he told The Daily Telegraph of London in 2011. “Then, at a later age, I picked up rugby.”

Meanwhile, he was on his way to becoming a surgeon, studying at the State University of Ghent, with a focus on the knee, “the most difficult joint to work on,” as he explained.

“I just liked the challenge,” he said.

One thing he dealt with as committee president was how much linkage there should be between a country’s government and its Olympic team. It was something he confronted when he was leading Belgium’s Olympic team in 1980, when President Jimmy Carter called for the United States and its allies to boycott the 1980 Olympics in Moscow over the Soviet Union’s invasion of Afghanistan. Belgium was such an ally, but Dr. Rogge pressed for the team to compete in Moscow anyway, and ultimately it did.

“This was a milestone in my life,” he said years later after becoming IOC president. “We thought it was our duty to participate in the Olympic Games. I still feel sorry for those athletes who were denied the Games they deserved. It gave me the resolve that, while we have to work closely with governments to develop sport, we have to preserve our independence.”

He confronted a similar issue in 2007, when there were calls to boycott the 2008 Games in Beijing over China’s human rights record.

“It is natural for human rights and other organizations to place their causes in the spotlight that the Beijing Olympic Games is casting on China, and to draw attention to reforms they advocate,” Dr. Rogge wrote in an opinion essay in The Times in 2007. “However, the Games can only be a catalyst for change and not a panacea. Any expectations that the International Olympic Committee should apply pressure on the Chinese government beyond what is necessary for Games preparations are misplaced.”

Dr. Rogge, who became a member of the International Olympic Committee in 1991 and joined the executive board in 1998, was elevated to the presidency not long after a scandal had erupted over the awarding of the 2002 Games to Salt Lake City. Members of the Olympic committee were accused of accepting gifts from backers of Salt Lake City’s candidacy.

Several committee members resigned or were expelled, but Dr. Rogge was untouched by the scandal, one of the things that made him an attractive candidate for the presidency. He replaced Juan Antonio Samaranch, who had held the post for two decades.

Dr. Rogge is survived by his wife, Anne Bovijn; a son, Philip; a daughter, Caroline; and two grandchildren.

Dr. Rogge made a conscious effort to project accessibility, including spending nights at the athletes’ village during the Games he oversaw. He was fluent in five languages and enjoyed eating in the group dining hall with the athletes.

“I take my tray and sit down at a table, and within a minute they come down and sit next to me,” he told The Telegraph in 2012.

“And they tell me what I should be doing,” he added. “What I hear mostly, and I know that they aren’t being hypocritical, is a plea to protect us from doping. The vast majority of athletes are authentic, and they don’t want doping.”