INDIANAPOLIS (REUTERS) - Sprinters seized the spotlight at the USA Swimming national championships with year's best times in Indianapolis on Thursday.

Lilly King won the 50 metres breaststroke in a 2017-best and US record time of 29.66 seconds, while Justin Ress swam the year's fastest men's 50m backstroke, winning in 24.41 to represent the US at next month's Budapest world championships.

King added the 50m national title to her triumph in the 200m race on Wednesday.

"It's awesome," said Olympic 100m breaststroke champion King, who also won the 200m race on Wednesday. "The 50 (breast) is just a splash and dash, so I get in and go literally as hard as I can. It was fun tonight. "I'm always happy to get the American record, and it was great to get that tonight, but I was hoping to be a little bit faster and hopefully get the world record. But I've still got a little bit left in the tank for Budapest."

Ress broke the national championships record to win his first US title. "It's crazy, I've actually always wanted to be a sprinter, but I swam distance in high school, distance my first year in college," said Ress. "My coaches put me in the mid-distance group my sophomore year. "Then I had a good 50 freestyle so they put me in the sprint group this summer and I've loved it so far." Kevin Cordes broke the US nationals record in winning the men's 50m breaststroke in 26.88 after previously winning the 200m breast on Wednesday.

Caeleb Dressel also won his second title of the meet by taking the men's 100m butterfly in another year's best time of 50.87 after claiming Wednesday's 50m butterfly.

Two of the longer races were also held, with Leah Smith winning the women's 400m Individual Medley in 4:33.86, while Chase Kalisz won the men's 400m IM in a year's best 4:06.99.