Rowdy Gaines and Tracy Caulkins put the Olympic boycott blues behind them tonight and each set an American record during the first day of competition at the U.S. Indoor Swimming Championships.

Gaines won the 100-meter freestyle in 49.61, the second-fastest time ever in the long-course sprint event. Jonty Skinner set the world record of 49.44 in Philadelphia in 1976.

Caulkins won her first event of the four-day meet at the Texas Olympic Swimming Center, the 200-meter breaststroke, in 2:33.06 to break her own standard of 2:33.88.

Caulkins and Gaines both said they would be in favor of going to the Olympics if the majority of athletes voted for such a proposal although Gaines said he would prefer the final decision be left to President Carter.

"I just wish the final decision would be made so we would know what to do," said Gaines, of Florida Aquatics.

The U.S. Olympic Committee is expected to make a decision concerning the Olympics Saturday in Colorado Springs.

The men's 200-meter butterfly featured the three medal winners at the 1976 Montreal Olympics plus the current NCAA and the Pan American champion. The oldest competitor of them all won. Mike Bruner, 23, the gold winner in Montreal, nearly broke the world record he set there of 1:59.23 when he charged past NCAA champion Par Arvidsson in the last 10 yards to win in 1:59.48.

Pan Am champion Craig Beardsley of Florida Aquatics also slipped past Arvidsson of Sweden to finish second in 2.00.44 with Arvidsson at 2:00.87.

Peter Roca, the silver medalist in the 200-meter backstroke in the 1976 Olympics, won that event here, holding off a strong charge by Mission Viejo, Calif., competitor Steve Barnicoat, Roca covered the last 50 meters in 31.41 to Barnicoat's 30.77 and set a record of 2:00.73 to 18-year-old Barnicoat's 2:00.85.

Roca, 22, of Concord, Calif., said, "I guess my arms might be a little longer than his, by just a couple of inches."