Katie Ledecky Sets Olympic Record in 400M Freestyle at 2016 Rio Games

American swimming star Katie Ledecky broke the women's Olympic record in the 400-meter freestyle on Sunday during the preliminary rounds of the 2016 Rio Games. 

Barry Svrluga of the Washington Post confirmed her time of three minutes, 58.71 seconds also came close to breaking the world record:

"My last stroke was a little lackadaisical," Ledecky told reporters afterward. "I shouldn't have done that. I'll be fine tonight."

The 19-year-old is one of the youngest United States athletes in Rio de Janeiro, but she isn't taking much time acclimating to the Olympic pressure.

The second-fastest swim of all time in said event is all the more incredible when one considers Ledecky most likely still has her best left to come—when the pressure is at its highest.

Her latest accolade came just a day after she helped set a new American record in the 400-meter freestyle relay, per the official USA Swimming Twitter account:

Ledecky missed her own world record by just 0.34 seconds, meaning it's hardly beyond possibility she'll make that extra time up and best her own time in the near future.