Michael Phelps will match his most grueling program since coming out of retirement, entering four events at next week's U.S. national championships.
The winningest athlete in Olympic history will compete in the 100-meter backstroke, 100 butterfly, 100 freestyle and 200 individual medley at the meet that begins Wednesday in Irvine, Calif.
"I feel good," Phelps told The Associated Press on Thursday. "Just staying relaxed is the biggest thing, not putting too much pressure on myself. I'm just going out and continuing what I've been doing throughout the year -- just having fun. That's how I've been able to swim my best."
The national championships, along with the Pan Pacific Championships in Australia a couple of weeks later, will determine the American team for next year's world championships.
Phelps retired after the London Olympics, having won a record 18 gold medals and 22 medals overall. He had accomplished all his goals and said he had no desire to swim into his 30s.
But he began plotting his comeback less than a year later, and began serious training last September.
Since announcing a return to competition in April, the 29-year-old Phelps has competed in four meets, swimming four events in one meet -- last month's Santa Clara Grand Prix. But this will be his most daunting program yet, giving him a chance to gauge just how far he has come in a relatively short period of time. His longtime coach, Bob Bowman, said Phelps has shaken off much of the rustiness in his technique, improving his starts and turns. Conditioning is the biggest question mark, especially as he takes on more events.
Phelps is more concerned with his mental approach.
"A couple of races, I've tensed up a little bit. I tried to take it super seriously and I didn't have good success in those races," he said. "Whatever happens, happens. There's going to be more heats, more training, where I can correct things if they don't go as planned next week."