Katie Ledecky competes in the women's 400-meter freestyle at the Rio 2016 Olympic Games at the Olympic Aquatics Stadium on Aug. 7, 2016 in Rio de Janeiro.





RIO DE JANEIRO — World records have been falling in almost every final in the Olympic Aquatics Stadium at the Rio 2016 Olympic Games. And in the 400-meter freestyle, Katie Ledecky did not disappoint.

In fact, with a three-second-plus gap on the rest of the field, Ledecky’s main foe is the world record.

From the moment she hit the water, the 19-year-old freestyle phenom left everyone in her wake — flying almost over the surface of the water, rather than through it, as if she has a different relationship with fluid dynamics than her competitors.

Her time, 3:56.46, lowered her world record by almost two seconds. And she won her second Olympic gold medal — and third to date. She has a gold medal from the 800 at the London 2012 Olympic Games, which she won when she was 15, and a silver from the 4 x 100 freestyle relay on the first night of competition here in Rio.

Ledecky became the fifth female swimmer to win gold medals at two different Olympic Games as a teenager.

When she looked at the scoreboard after the race, she felt “pure happiness.”

She had achieved a goal that she and her coach Bruce Gemmell had set three years ago after the 2013 world championships, where she won her first world title in the 400.

“Just to see the 56 up there feels really good,” Ledecky said in her usual succinct fashion.

Her coach Bruce Gemmell was equally succinct. When asked what he said to her after the race, she replied, “He said something like, ‘3:56 is pretty good.’”

Ledecky seemed happy for her teammate, Leah Smith, as well. Smith — who as a kid didn’t like to put her face in the water — swam the 400 in 4:01.92 and won a bronze medal, just behind Jazz Carlin from Great Britain who claimed silver.

“This is my first Olympics, so I still haven’t registered that I’m even here, let alone that I won a medal,” said Smith.

It was the first time in 16 years that an American has won an Olympic gold medal in the 400 free and also the first time in 16 years that two American women have stood on the podium together in the event.

Brooke Bennett and Diana Munz went 1-2 in the 400 free at the Sydney 2000 Olympic Games.

The 400 freestyle world record was one record that Ledecky had not touched in two years — the women’s 400 freestyle. She had lowered her other world records in the past year (in the 800 and 1,500 freestyle, which is not an Olympic event for women). But not in the 400 free. She came close at the 2016 U.S. Olympic Team Trials, swimming 3:58.98, the fastest time in the world this year coming into the Rio Games.

Ledecky’s previous world record in the 400 was 3:58.37 set at the Pan Pacific Championships in August 2014.

But 3:56 surprised no one who knows Ledecky.

“I trained with her for the past month,” said Smith. “The times that she put up in practice made me look like I was going to go 5 minutes. She is amazing. I knew she was going to go that time.”

Still, Smith was amazed when she saw 3:56 on the scoreboard and mouthed it in amazement as she hugged Ledecky in the pool.

Smith’s performance was almost as amazing as Ledecky’s, considering it was swimming in her first final in an international meet. A 21-year-old senior at the University of Virginia, Smith had bad jitters in the afternoon prelims, which made her tense. She struggled to the finish and didn’t even know if she would make the final.

Then Ledecky’s coach talked to Smith before the final.

“He was like, you’re swimming next to Katie, and that’s a position that you’re so comfortable in,” said Smith. “Normally when I swim, I like to be out front. But when I’m next to Katie, I still have really good races. If I’m anywhere near her, I’m probably having a good race.”

Smith swam solidly in third until the final 50, when she saw Boglarka Kapas from Hungary coming up in Lane 1.

“I was really nervous, but I wasn’t as dead as I was the last 50 of my morning swim,” she said.

She held on for the bronze, meeting her goal to bring home an Olympic medal for Team USA.

Ledecky has singlehandedly revived distance swimming in the U.S. The 400, 800 and 1,500 freestyle races were once dominated by legends such as Janet Evans, Shirley Babashoff and Debbie Meyer. But in the 2000s, distance swimming fell off the radar in the U.S. in part because NCAA programs typically recruit sprinters who can swim more relays and thus garner more points for their college teams.

At the Olympic Trials in late June, Babashoff gave Ledecky the ultimate praise. When Babashoff was training back in the mid-1970s in the Mission Viejo Nadadores’ program in California, she swam in what was called the Animal Lane, where distance swimmers pushed themselves to extreme lengths.

“She would have been in that lane,” Babashoff said of Ledecky. “She would have been the leader.”

Ledecky will return to the pool tomorrow afternoon for the heats of the 200-meter freestyle.

Although she is not favored to win gold in the 200, freestylers know to never count out Ledecky.

She is, after all, an animal.

***

When Dana Vollmer returned to the pool last April after having a baby, she coined her own hashtag: #MommaOnAMission.

Her mission?

To prove that she could be both an athlete and a mom.

After the women’s 100-meter butterfly at the Rio 2016 Olympic Games, Vollmer might want to change it to #MommaWithAMedal.

The 28-year-old butterflier earned an Olympic bronze medal in the women’s 100 fly — two steps lower on the podium than her finish at the 2012 London Games.

She finished in 56.63, over a second behind Sweden’s Sarah Sjöström, who broke her own world record by 0.16 seconds. The Swede won in 55.48.

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Vollmer’s 56.63 was 0.65 seconds slower than her gold-medal-winning swim in London four years ago. Her then-world-record time of 55.98 set at the London Games remains the American record.

It’s Vollmer’s first bronze medal and sixth Olympic medal overall. A three-time Olympian, Vollmer already has four Olympic gold medals — one from the 2004 Games and three from 2012 — and one silver medal from the women’s 4x100 freestyle last night.

A freelance writer based in Vermont, Peggy Shinn is in Rio covering her fourth Olympic Games. She has contributed to TeamUSA.org since its inception in 2008.