Katie Ledecky set an Olympic record during her 800-meter freestyle preliminary race Thursday.
Ledecky has already won four medals—including three gold—at the Rio games. During a heat for the 800-meter freestyle, Ledecky finished the race in an Olympic-record time of 8:12.86.
Earlier this week, Ledecky won gold in both the 200-meter and 400-meter freestyle. She also has a gold medal from the 4×200-meter freestyle relay, and a silver from the 4×100-meter freestyle relay.
In the 200-meter event, Ledecky set a world record.
The final for the 800-meter freestyle will take place Friday.