There they lay, completely oblivious of each other as they went through the repetitions of leg raises in a noon-time aerobics class. Another couple conversed politely while following the same routine.

Aren't men and women embarrassed -- or even a little self-conscious -- to be together in the same no-holds-barred class?

"I never found it stressful, while in leotards, to be with men," says immunologist Carol Nacey, a mother of five who works and takes the class at Walter Reed. "I have a good self-concept of body. It's very positive to have men around."

Nacey, 37, and sometime-exercise partner Col. Cliff Roberts, 44, who has worked with her for more than five years, see the classes as a break from "a stale working environment.

"I like it when there is a good mixed group," says Nacey. "The men have a lot more stamina for certain exercises and you put out that little extra effort because there are people around you. The men that are there are in tune with themselves. They're not self-conscious . . . I've seen plenty of men come in with no sense of rhythm and learn to coordinate arm and leg movements."

"I've had men go on from aerobics to African dance," says Melvin Deal, the founding executive artistic director of the African Heritage Dancers and Drummers in Washington. "They have said that movement is joyous, but movement with meaning is sublime."

In Eastern European ethnic dance groups, says Nicholas Jordanoff, artistic director of the Duquesne University Tamburitzans, the male takes on the dominant role in the folk dance.

"It's male chauvinism in reverse. The gals sit around in pretty costumes and are supportive."