Meanwhile, Turkey showcased 20 young people who are seen as the future of the country.
Tokyo is hoping to turn the spotlight away from the radioactive water leak at the crippled Fukushima nuclear plant in northern Japan, while Madrid is looking to fend off concerns related to Spain's high unemployment rate and economic struggles.
The Turkish city also has presented liabilities, facing questions about a string of embarrassing doping cases and a civil war in Syria on its border.
The host city will be picked on Saturday by the IOC.
Tokyo is seen as the favourite, although the race is viewed as too close to call as IOC members may settle for the bid with the fewest problems.
The IOC has said Tokyo presented the best technical bid, but members often vote along friendship lines, or for political or geographic reasons — shunning engineering studies or logistical concerns.
Yuki Ota, a two-time silver medallist in fencing, was one of a dozen athletes who appeared at a news conference to promote Tokyo's bid. She promoted Japan's doping record.
"I'm proud that no Japanese athlete has ever failed a doping test in the Olympics or Paralympic Games," Ota said. "I do not believe that education about doping can be achieved by one law alone. Long ago, Japan took action."
Ota was making a veiled reference to a recent anti-doping law passed in Spain.
Madrid has tried to deflect inquires about the 27 per cent unemployment rate in one of Europe's largest economies, and Gasol was quick to say the city's bid is "very strong" and poses "no risks."
Hosting the games, he added, could stimulate economic growth.
Gasol, a two-time Olympic medallist , is Madrid's biggest star athlete promoting the bid. He was also in the bid team in Singapore in 2005, when Madrid lost the 2012 bid to London. It lost the 2016 bid to Rio de Janeiro.
"I think we have grown from the time we lost in Singapore and maybe that will be decisive this time," he said.
Istanbul bid leader Hasan Arat shunned celebrities and introduced 20 young people as the face of Turkey. He said half of Turkey's population was under 25, and added that half of Istanbul's delegation at Saturday's final presentation to the IOC would also be under 25.
Arat sought questions from reporters, and the first dealt with recent street protests in Turkey. He asked high school student Esen Kucuktutunca to reply.
"That's kind of a normal thing," she said. "It's a democracy. People have the right to protest. It happened in London and lots of countries."
The students were also asked about press freedom in Turkey. Arat responded to the question himself.
"I'm not a politician, I'm a bid leader," he said.
AP Sports Writer Tales Azzoni contributed to this report.
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