SANTA CLARA -- Missy Franklin had a tough day of simulation Saturday at the Santa Clara Arena Grand Prix: back-to-back races at a distance of 200 meters.

It's what the soon-to-be Cal swimmer will face next month at the U.S. nationals, where she hopes to qualify in eight events for the 2013 World Championships.

"It's all about practice with this double," she said after winning the 200 freestyle and 200 backstroke to highlight another big day of racing at the George F. Haines International Swim Center.

The teen Olympic star sounded ecstatic after her victories. Another Olympic star sounded thankful to survive his double.

Ryan Lochte matched Franklin's exploits by winning the grueling 400 individual medley and the 200 backstroke.

Missy Franklin reacts after winning the 200 backstroke with a time of 2:08.24 during the 2013 Arena International Santa Clara Grand Prix at George F.
Missy Franklin reacts after winning the 200 backstroke with a time of 2:08.24 during the 2013 Arena International Santa Clara Grand Prix at George F. Haines International Swim Center in Santa Clara on Saturday, June 1, 2013. (Jim Gensheimer/Bay Area News Group) ( Jim Gensheimer )

But ...

"I forgot how brutal that is," Lochte said of the 400 IM, the event he won at the London Games.

While the middle-distance stars labored to secure impressive victories, Berkeley-based sprinters dominated the 50 freestyles. Nathan Adrian set his second meet record in as many days, winning a star-studded field with a time of 21.76 seconds. Natalie Coughlin won the women's sprint in 25.06, signaling the 12-time Olympic medalist's strength in the short distance.

Cal Olympian Caitlin Leverenz held off Stanford's Andrea Taylor to win the women's 400 IM in 4 minutes 40.05 seconds -- almost 21/2 seconds faster than Taylor.

But perhaps the most interesting event of the day involved Franklin's ability to handle so much. The Colorado teen also raced in the 50 freestyle in the morning preliminaries. But coach Todd Schmitz of the Colorado Stars had Franklin scratch the sprint in the evening.

He liked what he saw.

"It's a huge mental thing to get that hand on the wall," he said.

Franklin, 18, won the freestyle event in 1:58.26 by out-touching Olympic champion Allison Schmitt and Cal's Elizabeth Pelton. Five swimmers, including Walnut Creek's Chelsea Chenault, broke the 2-minute barrier in the race.

Ryan Lochte wins the 400 IM with a time of 4:11.36 during the 2013 Arena International Santa Clara Grand Prix at George F. Haines International Swim Center
Ryan Lochte wins the 400 IM with a time of 4:11.36 during the 2013 Arena International Santa Clara Grand Prix at George F. Haines International Swim Center in Santa Clara on Saturday, June 1, 2013. (Jim Gensheimer/Bay Area News Group) ( Jim Gensheimer )

"It's exciting," Franklin said. 'No one knows who will make the worlds team."

Franklin then blew away the backstroke field, winning in 2:08.24 -- almost 3 seconds faster than her closest competitor.

"Very few females can go 2:08" after doing the 200 freestyle, Schmitz said.

The effervescent Franklin said she welcomes the challenge.

"I love back-to-back racing," she said." It doesn't give me a lot of time to think."

She wanted to go faster in the freestyle but described the backstroke as feeling good the whole way. The four-time gold medalist was particularly happy with coming off the wall in a straight line.

"I didn't ping pong," she said of swerving on turns in the backstroke.

Lochte, who started training again six weeks ago, is feeling the pain of rounding into world-class shape. He built a commanding lead halfway through the 400 IM before North Baltimore's Chase Kalisz made a run. Lochte held on to win in 4:11.36, 0.49 of a second ahead of Kalisz.

"It takes guts to do that race," Lochte said.

His coach Gregg Troy of the University of Florida sounded pleased with Lochte's day.

"That was better," he said.

But he told his swimmer after the 400 IM, "That's a good time, but that was the worst way you could do that swim."

What was wrong with it?

"I swam like an age-grouper," Lochte said.

He took off too fast.

"Five more meters and I would have gotten third or fourth," Lochte added.

But like Franklin, the second part of the evening fared much better for Lochte, who finished third in the backstroke in London. He dominated Olympic champion Tyler Clary to win in 1:57.51. Clary was second in 1:58.02.

"I wasn't expecting that," Lochte said. "I felt like I had a lot more left."

Those who know Lochte don't doubt he does.

Contact Elliott Almond at 408-920-5865. Follow him on Twitter at twitter.com/elliottalmond.