Olympic athletes can express themselves at Games venues before the start of their competitions but not during medal presentations and other ceremonies and in the athletes’ village.
It said athletes can for the first time express themselves “on the field of play prior to the start of the competition (ie after leaving the “call room” (or similar area) or during the introduction of the individual athlete or team).”
It means that athletes could take a knee or raise a fist in that limited period.
Athletes can also speak out in interviews and on social media during the Games.
The IOC added: “When expressing their views, athletes are expected to respect the applicable laws, the Olympic values and their fellow athletes.”
Athletes who violate the guidelines face sanctions, including disqualification and being stripped of medals, according to the Olympic Charter.
“Disciplinary consequences for participants may be as set out in the Olympic Charter and will depend in part on the findings of the above evaluation,” the IOC said.
“Participants may expect that any sanction will be proportionate to the level of disruption and the degree to which the infraction is not compatible with the Olympic values, including the fundamental principles of Olympism.”
IOC Athletes’ Commission chairwoman Kirsty Coventry said: “While the guidelines offer new opportunities for athletes to express themselves prior to the competition, they preserve the competitions on the Field of Play, the ceremonies, the victory ceremonies and the Olympic Village.
“This was the wish of a big majority of athletes in our global consultation.”
This means that for instance a raised fist protest on the podium like at the 200m medal ceremony in 1968 from Americans Tommie Smith and John Carlos remains outlawed.
The IOC has stopped short of scrapping its rule 50 althogether which says that “No kind of demonstration or political, religious or racial propaganda is permitted in any Olympic sites, venues or other areas.”