BARCELONA, Spain — After swimming nearly a mile, Katie Ledecky knew it was time to get going.
Did she ever.
Looking stronger at the end of the grueling race than she did at the beginning, the 16-year-old American obliterated the world record in the 1,500-meter freestyle by more than 6 seconds Tuesday night for her second gold medal at the world swimming championships.
"She's absolutely fit," marveled Mereia Belmonte of Spain, who finished far back in fourth. "Impressive. She's probably made in the same factory as Michael Phelps."
Missy Franklin picked up her second gold medal, as well.
Cruising through a demanding double, the 18-year-old star of the London Olympics easily won the 100 backstroke, then returned about an hour later to post the second-fastest time in the semifinals of the 200 free.
"It's tough but it's fun," Franklin said. "I'm super happy with my 100 back. It really got me pumped up for the 200 free."
It was a good night for the Americans after they failed to win gold the previous day.
Matt Grevers and David Plummer went 1-2 in the 100 backstroke for the third U.S. victory of the session. Conor Dwyer picked up a silver behind France's Yannick Agnel in the 200 free, and Jessica Hardy chipped in with a bronze in the 100 breaststroke won by Lithuania's Ruta Meilutyte.
The only disappointment for the U.S. was Ryan Lochte, who labored to a fourth-place finish in the 200 free.
"It wasn't my night," the three-time Olympian said. "But I have to put it behind me because I still have many races to swim."
He hopes to compete in seven events in Barcelona, despite not being able to train as much as usual this year while taking part in his reality television show, "What Would Ryan Lochte Do?"
No such concerns for Ledecky, who is clearly in top form. She went stroke for stroke much of the race with defending world champion Lotte Friis, the Danish swimmer slightly ahead and both well under the world-record pace set by Kate Ziegler in 2007.
Ledecky edged out front at the 1,300 mark and began to pull away, touching in 15 minutes, 36.53 seconds. A woman ran through the crowd with a blue flag that proclaimed "World Record" — Ziegler's mark of 15:42.54 never standing a chance.
Friis also went under the old record, 15:38.88, but it was only good enough for silver. New Zealand's Lauren Boyle took the bronze.
"Around the last 200, I knew I could take off," Ledecky said.
The 1,500 is a non-Olympic event — the longest women's race at the Summer Games is the 800 — but that made the achievement no less impressive.
Ledecky looks even stronger than she did last year while winning Olympic gold in the 800 free, a stunning breakthrough for someone barely known on the international stage.
Naturally, after that performance, she arrived in Barcelona dealing with the weight of expectations. Plus, she decided to take on an exhausting program that also includes the 400 and 800 free.
Not to worry. Ledecky nearly broke the world record while winning the 400, and she'll be a huge favorite in the 800 — a worthy successor to Janet Evans and the proud U.S. history in the women's distance events.
"It was really tough, my hardest race ever," Ledecky said. "I knew we were going pretty fast and I figured that whoever was going to come out on top was probably going to get the world record. So I just had to be careful not to push it too early or push it too late and just touch the wall first."
Franklin breezed to victory in the 100 back in 58.42 seconds. After capturing four golds and a bronze at the London Olympics, the recent high school graduate is trying to join Phelps as the only swimmers to win eight events at a major championship. She is now 2 for 2 at the Palau Sant Jordi, adding to her gold in the 4x100 free relay.
Australia's Emily Seebohm was next in 59.06, with the bronze medal going to Japan's Aya Terakawa in 59.23.
After the medal ceremony, Franklin hustled off to get ready for the 200 free semifinals. She barely qualified for the final of that event in London, and was edged out for a bronze medal by one-hundredth of a second.
Franklin has spent much of the past year working to improve her freestyle, and the results showed in the semis. Franklin easily qualified for the final with the second-fastest time, 1:56.05, trailing only world-record holder Federica Pellegrini of Italy.
"Hopefully, I will keep the momentum going," Franklin said. "Hopefully, Team USA will, too. We've had an absolutely incredible evening, and I'm so proud of all my teammates."
Agnel blew away the field — Lochte included — in the men's 200 free.
The big Frenchman pushed the pace right from the start and never let up. He touched in 1:44.20, a full body length ahead of the field, setting off another wild celebration from the large French contingent in the crowd.
The Americans did pick up a medal, but not necessarily from the swimmer they expected. Dwyer, a friend and former training partner of Phelps, took the silver in 1:45.32. Danila Izotov of Russia claimed bronze in 1:45.59.
Lochte missed a spot on the podium by 0.05.
Agnel is actually a training partner of Dwyer's, having moved recently to the North Baltimore Aquatic Club to work with Phelps' longtime coach, Bob Bowman.
"I am so surprised," said Agnel, the reigning Olympic champion. "I did not expect such a result."
Meilutyte just missed the world record she set the previous night in the semifinals of the 100 breast, winning in 1:04.42. Russia's Yuliya Efimova was next in 1:05.02, while Hardy — the former world-record holder — pulled out a bronze in 1:05.52.