BEIJING (AP) Tom Daley's age hasn't been an issue. The British Olympic diver is 14 and his youth - his braces were only recently removed - makes his story compelling.
Nor has anyone made a fuss about Antoinette Joyce Guedia Mouafo. At 12, the swimmer from Cameroon is the youngest athlete in the Beijing Olympics and had never swum in a 50-meter pool.
Then there are the three female Chinese gymnasts - He Kexin, Jiang Yuyuan and Jang Yilin - who won gold for China in team gymnastics. The rules dictate that gymnasts must turn 16 during the year of the Olympics in order to compete, but photos, competition records and past media reports suggest the three Chinese gymnasts might be much younger.
The IOC and the body that governs world gymnastics say their passports prove that they meet the age requirement.
Age rules at the Olympics are set by the federations that run the sports, and many don't have any limits.
The gymnastics age requirement was adopted following criticism that girls 14 and under were being exploited. It is supposed to protect the physical and psychological health of young athletes - primarily young women whose bodies are still growing.
Figure-skating has a minimum age of 15 for similar reasons.
"It's a matter of health and taking care of the gymnast," said Philippe Silacci, spokesman for the International Gymnastics Federation. "I think I can make the point this way: Try to put a 12-year-old boy in a Formula One car and see what happens."
Nadia Comaneci was 14 when she won her first Olympic gold medal in 1976. Despite Comaneci's stardom, the sport was criticized and sometimes even athletes under 14 were given exemptions to compete.
"There was quite a bit of media attention, especially in Europe, about these young children comparing them to kids that used to work in the coal mines in the 18th and 19th century," said Hardy Fink, who heads the education program for world governing body.
FIG raised the minimum age from 14 to 15 in 1981. In 1997, it went to 16. Boosting the minimum age was supposed to encourage coaches to go easier on younger athletes.
U.S. Olympic gold-medalist Bart Conner has his doubts.
"In many ways it was a knee-jerk reaction from the gymnastics federation to remind coaches to not push so hard," Conner said. "But I'm not sure that's really worked. I'm not sure if, in the gym, that causes a coach to back off a little. Maybe it does.
"The logic makes sense. But I'm not sure it works."
Setting age minimums can also create a different problem - age falsification.
Reports of the practice go back several decades, involving primarily gymnasts from eastern Europe. Chinese gymnast Yang Yun, who won a bronze medal in the 2000 Olympics, later acknowledged in a television interview that she was 14 when she competed in Sydney.
Arne Ljungqvist, head of the IOC medical commission, said age-manipulation is a problem that's tough to detect. Ljungqvist runs the IOC's effort against doping and concedes age manipulation is another form of cheating.
"This is a problem when you have an age limit that there is a temptation for manipulation," Ljungqvist said. "How to prove that is very difficult. There are ways and means of establishing the age, or the supposed age of a person, but it isn't absolutely scientifically accurate - nor a legally accurate way of doing it."