2022 U.S. Swimming World Championships Trials: Katie Ledecky wins 400m freestyle with fastest time in 2022

It's day four of the U.S. Swimming World Championship Trials at the Greensboro Aquatic Center on Friday (29 April) as the top US swimmers continue their quests to be named to the 2022 World Championships in Budapest. The Worlds begin June 17 and run through July 3.

The competition kicked off on Tuesday morning and will conclude on Saturday night with the top two finishers in each individual event being selected.

Check out what happened on Thursday.

Olympics.com will provide you with regular updates of the action.

Here is everything you need to know about the event.

6:56 pm - Day four concludes with backstroke wins for Smith, Armstrong

Regan Smith broke her own U.S. Open record, set at last year's U.S. Olympic trials, in the women's 100m backstroke with a 57.76 swim. Claire Curzan was second at 58.39.

"It feels really great. My backstroke has felt awesome this week. I knew I had my work cut out for me coming into this really talented field, and I'm just really pleased with my performance," said Smith. "It's absolutely crazy to have so many of these girls in this field be top five in the world, top eight in the world. It's really great to be able to race against all of them."

In the men's 100m backstroke, Hunter Armstrong and Ryan Murphy finished first and second with times of 52.20 and 52.46, respectively. Those are the two fastest times in 2022 so far.

"I got a really good nap in between prelims and finals," Armstrong joked of the secret to his success in Greensboro where he also set the world record in the 50m backstroke yesterday.

"I did not sleep any at all [after setting the world record], but that's one thing that I'm going to have to start getting used to," said Armstrong. "I spoke to Ryan [Murphy] earlier because obviously he has the record in the 100 back, I'm like, 'How do you follow up swims like that?' He's like, 'Eventually, you'll get used to it.'

"I don't know that I'm anywhere close to that yet," he concluded.

6:47 pm - Fink upsets Andrew in 100m breaststroke

Nic Fink swam a personal best 58.37 to win the men's 100m breaststroke ahead of American record holder Michael Andrew (58.51). Their times are the two fastest so far in 2022. Fink, 28, won three gold medals last year at the short course world championships, including in the 50m and 200m breaststroke.

"I was happy with that for sure, surprised to see that. It's been a great meet so far, every race has been a battle. I wasn't expecting anything different here," said Fink. "The takeaway is, I gotta be ready to do all that again in a few more weeks."

6:37 pm - Olympic champion Jacoby finishes fourth in 100m butterfly

Tokyo 2020 100m breaststroke gold medallist Lydia Jacoby failed to qualify to the world championships after finishing fourth in the event in Greensboro. Instead, Team USA will be represented by Lilly King (1:05.67) and Annie Lazor (1:06.12), who finished first and second, respectively. The pair train together in Indiana.

"It's awesome, this is what we train to do. I was joking with her because we kind of did this at trials last year. I was like, 'Let's not put this pressure on ourselves next year.' Just super proud and excited to be racing again," King said afterward.

6:26 pm - Smith wins men's 400m free

Kieran Smith, the 2020 Tokyo bronze medallist in the event, clocked a 3:46.61 to win the men's 400m freestyle, holding off Florida training-mate Trey Freeman, who surged at the end. The pair were separated by just .32 seconds, as Freeman's time was 3:46.93.

"I didn't know it was going to be dramatic. I was just racing Ross [Dant] really," Smith said with a laugh. "I kicked off hard the last wall, I was kicking really hard. Look up, and my teammate is second and I'm really pumped about that."

Earlier in the event, Smith won the 200m free.

6:12 pm - Ledecky takes comfortable win in 400m

Katie Ledecky, the 2016 women's 400m Olympic champion, got the evening off in fine form, becoming the first woman in 2022 to swim a sub-four minute time in the 400m. She hit the wall at 3:59.50. Leah Smith recorded her third top three finish of the meet, taking second place at 4:03.15.

"It's great. I wanted to be under four [minutes], I felt like I could after this morning's swim. I'm happy with that," said Ledecky on U.S. broadcaster Olympic Channel.

She also said she agreed with three-time Olympic champion and NBC commentator Rowdy Gaines' assessment of what makes her so good: a love of the - at times - monotonous work.

"I love the sport, I love the training. I think over the last 10 years, I've probably taken no more than about two weeks off. That tells you how much I truly love it and love the day-to-day, working with a really great group in Florida right now."

1:05 pm - Ledecky dominates 400m free in prelims

Seven-time Olympic gold medallist Katie Ledecky was dominant in the 400m freestyle prelims Friday (29 April) morning, winning the heats by more than four seconds over second place Leah Smith.

Fellow Olympic champion Lilly King also won in the prelims, taking the top spot in the women's 100m breaststroke, while Olympic champion Lydia Jacoby was the fourth-place finisher in the heats. Michael Andrew was the fastest in the men's 100m breast.

In the 100m backstroke, Regan Smith was the top qualifier in the women's field with Justin Rees and Ryan Murphy finishing 1-2, separated by just .07 in the men's race.

Day four features busy schedule

Here's what's on tap for Friday's competition, all times are local to the event (ET).

Prelims Schedule:

9:00am - Women's 400m Freestyle
9:23am - Men's 400m Freestyle
9:54am - Women's 100m Breaststroke
10:10am - Men's 100m Breaststroke
10:24am - Women's 100m Backstroke
10:42am - Men's 100m Backstroke

Finals Schedule:

6:07pm - Women's 400m Freestyle
6:22pm - Men's 400m Freestyle
6:34pm - Women's 100m Breaststroke
6:43pm - Men's 100m Breaststroke
6:52pm - Women's 100m Backstroke
7:04pm - Men's 100m Backstroke