Ten minutes before the beginning of the Mid-Atlantic Regional Disco Finals, Vicki Van Mater crumples in a faint to the floor of the Plum Club in her coral chiffon dress.

For the past two weeks, Van Mater, who is 28, has practiced every day, two to three hours a day, with her partner, Doug Pelton. They have practiced one single routine for the contest for 20 hours. Under the tutelage of their coach, Fred James, Van Mater has stood in front of a mirror in his studio and worked. She would fall, she would slip. She has worked hard.

She started entering disco contests two years ago with Pelton, back when the hustle was popular and when the contest prize was often a bottle of wine. But two years, 50 contests and 40 wins later; 25 dinners for two and a total of $2,000 in cash and prizes later, Van Mater and her partner are competing in a contest that might send them to a national contest at the Roseland ballroom in New York. And if they won they would go to an international contest in London and possibly win more money than they have won total in the past two years.

As she lies on the floor, people cluster around. Slowly they raise her to her feet. James, her coach and former jitterbug champion, a large man dressed all in black, puts a firm arm around her shoulder and pulls her close to his chest.

"Breathe," he said firmly in her ear, heaving his chest slowly and steadily. "Breathe." She follows his orders, taking deep, slow breaths, smiling wanly. Gingerly, but still smiling, she sits in her seat at a table two feet from the dance floor, making little jokes about how dangerous disco dancing can be.

A few minutes later, their number is called, and Van Mater and Pelton waft onto the disco floor, as if in slow motion. Her floaty, revealing coral dress, which she designed and made, is slit all around and as she moves, it lifts up in little clouds. With coral sequins on her shoes, a coral flower in her hair, and coral nail polish, she could be a beauty contestant.

Doug Pelton, in matching coral pants and coral vest trimmed with sequins on the back, moves toward her, across a tiny square-shapped wood floor, floor-to-ceiling mirror-faceted pole in the middle.

Van Mater, still quesy, leaps into Pelton's arms and then onto his shoulders to the opening dreamy-sounding music of "Last Dance" by Donna Summer. As the tempo picks up, Pelton literally picks up his partner and they swing into a "flying vicki." her legs swing high-heeled shoes, perfectly placed together, jostle the ceiling lights. Peltons's blond-haired mother, also in a coral dress, darts around the floor taking pictures.

For the finale, Van Mater leaps backward into Pelton's arms as he kneels on the floor. The music stops, the audience goes wild with applause and screams. Vicki Van Mater, her smile turning into a grimace, goes off in search of a bathroom.

"Hmmm....We were good," Doug Pelton appraises solemny from the side of the dance floor, his arms wrapped around his partner and girlfriend, as they wait for the judges' decision. "We did everything we wanted to do. We think we made three noticeable mistakes, mainly in timing."

Van Mater, who lives in an apartment in Reston and works for an awards crafter in Fairfax, and Pelton, 24, who lives with his father in Silver Spring and works for the Fairfax Circle Banquets, a catering firm, were one of 11 couples in the regional contest. The couples came from Baltimore, Delaware, and Virginia, as well as Washington. One couple never made it to the dance floor because of a broken shoe.

The six judges awarded points to each couple on the basis of "originality, rhythm, and costume."

The six judges were the president of a savings and loan association, a former Redskins player, a disco dance teacher and former Plum contest winner, a dance instructor from the Fred Astaire studios in Baltimore, a representative of another disco club, and the host of a disco radio show.

Then the announcer read the names of the runners-up and asked that when their song was played the winners were to return to the floor. When the dreamy strains of "Last Dance" wafted out again Pelton walked out onto the floor affecting surprise. Van Mater, still smiling, walked out onto the floor looking relieved.

Pelton met Van Mater 21/2 years ago at the Bombay Groove, (now Studio 50) in Virginia. He already had mastered the Bump and the Hustle and was learning the Latin Hustle when he met Van Mater. "She's never danced before in her life," he recalled.

"I was just too embarrassed to get up and do all that," she said. "This separate dancing didn't look nice, but when I saw them dancing the hustle, it was feminine and romantic and the girl had as much importance in leading the dance as the guy had."

They started dancing twice a week.

Two months ago, they went to Fred James for lessons which have cost them an average of about $30 a week. "We wanted someone to look at us for line," Pelton explained.

"Doug and I both wanted to do well," Van Mater said, pounding the table gently with her fist. "When you really want to do it right it's not hard."

"We have to do gymnastics for competition," said Pelton, "and that puts a lot of pressure on you. We put about 20 hours of practice into this one routine."

They go to clubs almost every night, particularly searching them out on the less crowded, less popular nights.

Van Mater picks expensive leather shoes, preferring ballroom shoes with suede bottoms, and goes through one pair in three months on the average. "These are good," she said, tapping the $42 pair on her feet.

"Ive got to admit I'm not really into the disco-disco scene," Van Mater said smiling. "I like the music, but I don't like it so loud. I don't like the flashing lights. They make me dizzy. But I lu-huuuve to dance. I don't spend any more money on dancing than other people do on any other sport. In fact I probably spend less. When I'm actually dancing, nothing else matters. Everything flows. You just transcend the everyday experince. When you start competing, it gets tough."

"But when I'm working on a routine that goes right," she said, "everything else flows. I can't explain it. I need words!" She grasps at the air with her hands. "It's like having the ultimate experience, and the more you know when you dance the more you experience."