Somehow, many of the moments didn't seem right.

The hours of sitting around in the lobby of the Marriott Twin Bridges Hotel, waiting to get into their rooms at 4 p.m.

The bus driver, providing the quiet athletes with a night tour of Washington, telling them how polo players come down to Potomac Park on weekends, how you can watch them play for free.

The five tables stocked with gallons of Haagen-Dazs ice cream at the Prospect House reception Saturday night, each equipped with bowls of chocolate syrup, butterscotch and whipped cream, so that hundreds of Americans who had expected to be in the top shape of their lives this week could stuff themselves with sundaes.

Saturday afternoon, nearly 500 of American Olympians began arriving at the Marriott Twin Bridges for five days of receptions; shows, dances, free clothes and clinics, a $950,000 attempt by the financially hard-pressed U.S. Olympic Committee to put smiles on the faces of its athletes, to make it up to them with a kind of high school trip of the century. Each athlete even gets to bring two guests, who may arrive Tuesday and stay through Thursday morning. But as the athletes checked in Saturday and began to decipher their tightly arranged scheduled for Day One, no one pretended that competing isn't the most important thing.

"This is no alternative," grouched 258-pound judoist Jesse Goldstein, who plunked sulkily with some of his teammates and women's field hockey goalie Diane Moyer on cushioned chairs by the hotel's front desk. "This is a party."

Moyer, whose 22nd birthday on Tuesday will not be quite what she expected, looked as glum as Goldstein. She explained that she found out she had made the team on Jan. 3., a day before the bad news first came that the United States might not go to Moscow. Facing graduate school in psychology at the University of Massachusetts this fall, she expects training for 1984 to be much harder for her. Still, she felt less harshly about the week's planned events than some of her colleagues.

"If you come in here with the attitude that you're going to show Jimmy Carter," Moyer says unenthusiastically, "you're not going to get anything out of this."

According to Brooke Newell, a Chase Manhattan Bank vice president who helped organize much of the "Olympic Honors Program," 95 percent of the Olympians are coming, not counting the swimming team, which is holding its finals in California. More than 200 got squared away at the hotel in time to board buses to the Marriott Key Bridge for dinner.

On one, members of the weightlifting team, not happy about a perceived broadening of press coverage of the Olympics, sidetracked attempts to get their names straight while pouring out their complaints.

"It shows no respect for us," sad one. "I wish the press hadn't covered it at all. And there's no such thing as an alternate Olympics. This alternate Olympics crap is just stuff to soften the public.

He agreed, somewhat resentfully, with the suggestion that it must be difficult to stay in shape after such a great disppointment.

"Would you write better if you didn't have a job?" he shot back.

The fourth busload of Olympians reached their dinner destination just as another bus emptied a large group of athletic-looking males into the Key Bridge hotel. Mostly smiling. Hair very short. Not the men's swimming team.

"The You-nited States Marines," a fellow with arms to equal the weightlifters' told a little girl at the door who braved the question of what team they were on. On leave from Quantico for the day, they went right and Olympians went left, to an evening meal of fruit salad, roast beef and cake. An hour later, it was back on the buses for a tour.

"This is better than nothing I guess," yawned 14-year old Tracee Talavera of the woman's gymnastics team, her 74 1/2 pound frame in no danger since she has to "stay away from all the junk." Teammate Julianne McNamara also thought the Washington activities were some compensation. But by the time the bus passed the Jefferson Memorial, McNamara slept quietly with Talavera tottering on the edge herself one seat behind.

38 Olympians on the lead bus talked little on the tour, in part because few knew each other. Brian Bungam and Amy McGrath, both divers, discussed the difficulty of staying motivated for the Olympic finals this year. McGrath, subdued, expressed her annoyance at the shoulder-shrugging of some people about the whole thing. "They act as though if you don't go this year, you can just go in four years," she said. "But what guarantee is there that you'll make it?"

Larry Gerard, a University of Nebraska gymnast and architecture major, kept his eyes peeled on the stately buildings along the tour. He's been angry about the way he feels the Russians have manipulated gymnastics scores with the Americans absent, giving 10s, he said, for tricks that involve no originality. Gerard knows its the end of the line for him in his sport. "I'm here to get some of the things I knew I'd get at the Olympics."

Both on the bus and at the poolside reception, many of the athlets turned acerbic about the gold medals each will be getting from Congress and the cowboy outfits that they are supposed to wear while receiving them. Many wish to make clear that their coming to Washington does not mean they support the president's decision to keep them home. Members of the women's rowing team, who helped lead the doomed fight to go to Moscow over presidential opposition, declined to reveal whether rumors of a protest at Wednesday's White House reception are true. "Surprises are nice," quipped Anita De Frantz, the rower/lawyer at the forefront of the movement.

Dan Chandler, a 28-year old wrestler from Minnesota who had hoped the movement would succeed, blamed its failure on the inability of the Olympians to match the communications resources of Olympic administrators "with all their WATS lines." He's here, like Gerard, because it's most likely the end of his Olympic hopes and he wants to make the best of things. For all that, he can't help finding some of the gestures, "pretty weak."

"When I look at the gold medal 20 years from now," he says, indifferently, "I don't know what I'm going to think."

Few of the Olympians felt like dancing on the small floor set up in Prospect House's back yard. They sat at tables by the pool, or walked in the garden, exchanging information about performances in Moscow or rehashing how their ambitions had been blocked. Around midnight, a reception organizer began shepherding the athletes back to the buses. A few rowers were becoming slightly boisterous near the pool, and she was afraid someone might end up in the water.