Of the approximately 11,000 athletes who competed in Rio, at least 120 had served suspensions or had to return medals because of doping but were reinstated in time for this year’s Games. This was about one out of every 100 competitors.

31 of These Athletes Won Medals in Rio

Of the 974 medals awarded, 35 were won by athletes whohad served suspensions for doping.

Rio medalists who have served suspensions for doping Period of suspension Olympic medals won Medals stripped

Some of these athletes were openly criticized by their fellow competitors in Rio. In the swimming competition, Yulia Efimova of Russia and Sun Yang of China were the targets of pointed comments.

Efimova, 24, won silver medals in the 100-meter and 200-meter breaststroke events.

She has served a 16-month suspension for doping, and she tested positive this year for the newly banned substance meldonium.

Yulia Efimova of Russia in a preliminary heat in the 200-meter breaststroke. Dominic Ebenbichler/Reuters

Initially, Efimova was barred from Rio, along with six other Russian swimmers, who either had positive tests on their records or had been named in an investigation of a massive state-sanctioned doping scheme. But a last-minute ruling allowed them to compete.

Efimova was booed every time she raced in Rio and was the object of public derision from the American swimmer Lilly King.

Sun, 24, was called a “drug cheat” by the Australian swimmer Mack Horton before the men’s 400-meter freestyle. Horton won the gold medal, and Sun placed second. Horton called it “a win for the good guys.” Sun later won a gold medal in the 200-meter freestyle.

Sun Yang of China receives his gold medal in the 200-meter freestyle. David Gray/Reuters

Almost One-Third of the Countries That Participated in the Rio Games Had Athletes Who Were Previously Suspended for Doping

At least 63 of the 205 countries in the 2016 Olympics had athletes who had served suspensions for doping. The United States, had the second most, with seven, after Ukraine, which had eight.

Countries with athletes in Rio who have served suspensions for doping Russia Norway Canada Belarus Britain Poland Germany Ukraine Kazakhstan France Serbia Uzbekistan Italy Spain N. Korea Turkey United States Turkmenistan S. Korea Syria China Iran Morocco Qatar India Jamaica Sudan Thailand Nigeria Venezuela Cameroon Colombia Malaysia Tanzania Brazil Peru Australia South Africa Uruguay Russia Norway Canada Belarus Britain Ukraine Kazakhstan Germany Serbia Italy Spain N. Korea Turkey United States S. Korea Syria China Iran Morocco Qatar India Jamaica Sudan Thailand Nigeria Venezuela Cameroon Colombia Malaysia Tanzania Brazil Peru Australia South Africa Uruguay

One of the more prominent Americans in this group was the sprinter Justin Gatlin, this year’s silver medalist in the 100 meters. He has been twice suspended for doping, once for four years. Fans booed him as he took the track ahead of the 100.

Another American, Tyson Gay, was caught doping in the London Olympics in 2012. That cost the United States team its silver medal in the 4x100 relay. Gay ran with Gatlin in the same event in Rio on Friday.

Justin Gatlin, left, handing the baton to Tyson Gay in the 4x100-meter relay at the 2012 Olympics. Hassan Ammar/Associated Press

It is worth noting that the United States has one of the largest delegations at the Games. The percentage of its team that is on this list is less than 2 percent.

More suspensions are not necessarily an indication that a country has more athletes who are doping. Suspensions can also be a gauge for how strong the drug-testing program is in a given country.

Russia most likely would have had more athletes on this list if its full delegation had competed in Rio. Nearly one-third of the Russian team was barred by various sports federations after investigations revealed an extensive state-run doping program.

Athletes that have been suspended for doping Period of suspension Olympic medals won Medals stripped

The analysis by The New York Times matched names of athletes who had served suspensions for doping with the official roster for the Rio Games. The names of suspended athletes came from the Anti-Doping Database and from official statements from national and international sport federations.