Five world records in five days of Olympic swimming is tame compared to the 25-record bonanza in Beijing, but swimmers say it shows the ban of high-tech bodysuits hasn't stopped progress.
"I think swimming is such a persevering sport and we are able to push our boundaries and make higher limits for ourselves," said US teenager Missy Franklin, whose international debut in 2010 came after bodysuits were banned.
"I think it is great we have been able to come out here and show the world, hey, we don't need those suits to do those times."
After Beijing, where the part-synthetic Speedo LZR bodysuits were in use, a later generation of all-polyurethane suits contributed to 43 world records at the 2009 world championships.
Pessimists predicted the records set in the buoyant, muscle-compressing suits would linger on the books for years.
But USA Swimming's national team director Frank Busch said that view didn't take into account the sheer determination of swimmers to swim fast.
"Never underestimate an athlete when the bar has been raised," Busch said. "And never underestimate their coaches either."
{{/usCountry}}"Never underestimate an athlete when the bar has been raised," Busch said. "And never underestimate their coaches either."
{{/usCountry}}Busch said he'd even come to see the bodysuits as "a bit of a blessing" because the times had broken down barriers in swimmers' minds. Daniel Gyurta won 200m breaststroke gold in a world record of 2:07.28 and Rebecca Soni clocked a world record of 2:20.00 in the semi-finals of the women's 200m breast.