At first they tried to ignore each other. The two 10-year-old girls, wearing identical riding outfits -- black cap, blazer and knee-high boots -- stood side by side, grooming their ponies for the next competition in the Middleburg National Horse Show.

"You know my pony is better than your pony," said the shorter one, breaking the tense silence. She flung her long, strawberry-blond braids over her shoulder. "I'm going to win and win big."

The other girl's freckled face reddened. "That's not true," she shouted, her eyes filling with tears. "You'll see. I hope you fall off and break your neck."

Neither of them won anything.

The annual five-day event with 133 competitions ended yesterday, and featured about 1,000 riders of all ages, some from as far as California and Hawaii. The events included everything from children's lead line to advanced sidesaddling. These aren't just any riders, said 12-year-old Beth Creekmore of Virginia Beach. These are among the finest in the country. Their horses are among the finest anywhere. The competition on the grounds of the Foxcroft School is the big-time of the horse show circuit.

"After all," she added with a long sigh, "everyone knows that Middleburg is the horse capital of the United States."

"If you do good here," said 9-year-old Carol Campbell of Roseland, Va., "it means you're good."

The parents, who have invested thousands of dollars and thousands of hours in their children's equestrian talents, want them to be more than good. They want them to be the best. "I've put a lot of energy into this," said Lynne Lande, of Atlanta, whose 17-year-old son Jay is the leadinghorse rider in the country for his age group. "When he gets a ribbon, I feel great. Oh, do I feel great inside."

Nervous mothers and fathers stood outside the fence, cheering at their child's moment of glory. "You're doing beautifully, little Muffin, keep it up," screamed a burly man in lime-green Bermuda shorts and matching T-shirt. His wife, wearing a jump suit with a horse pattern, closed her eyes and nibbled at her nails.

Muffin waved vaguely and smiled, her braces glistening. The 9-year-old has been riding since age 3. For every birthday, her father said, he buys her a new pony. He intends to continue the tradition until she turns 21. "She's a natural," he said. "Have you ever seen anything so beautiful in your life?"

"Yes, I have," snapped another father. "She'll be out in a few minutes and you'll certainly change your tune."

Then, there are the professionals, like 29-year-old Brian Lenehan of Warrenton, Va. -- winner, along with his horse Athabasca, of the Peggy Latham Memorial Trophy. The bronze equine statue is presented each year to the local horse with the highest number of points. Lenehan, who said he has been riding "forever," seemed pretty nonchalant about the whole thing. That's how one can distinguish the pros from the amateurs.

"After a while, you get used to all of this," he said. "It becomes fairly routine."

Lenehan, born into a "horsey family," grew up on the road, traveling from show to show. Now he attends about 20 each year. The hectic life style hasn't hurt him socially, he said. If anything, it's helped. "I know people all over the country. My closest friends are people I met on the circuit."

The people -- not the money -- are why he stays in this business, he said. "Most times, the cash prizes aren't enough to keep you going when you consider the high living of the circuit." In addition to riding, he trains horses and judges competitions.

"The money isn't the lure at all," he repeated. "It's the great friends. And, of course, we all love to win." A long pause. "Let's face it, that's why we do this. We're in it to win."

Whether male or female, young or old, professional or amateur, the talk is the same -- horses and winning. "No one wants to be a loser," said 22-year-old Darlene Simons from Denver, who said she started riding right after she learned how to walk. "No one even wants to be second place. Not after all the blood and sweat that goes into training."

But after finishing high school, Simons stopped competing in shows. "I got tired of breathing and sleeping horses," said the slender blond, sporting a new "Lady Di" haircut. "I wanted to talk about growing up, about guys. I wasn't able to make the thousand percent commitment to this anymore and it showed in my performance."

Simons gave the pony, "Sugar Babe," to her 8-year-old niece, who said she rides three hours each day and all day weekends. Next summer, she will make her debut on the circuit.

"Then she goes into high gear," Simons said, adjusting the girl's pony tails. "No more Barbie dolls for you."

She winced.

"Oh my God, what a beautiful jacket," screeched a middle-aged woman, throwing her arms around Simons. "It's absolutely divine. It must be a Pytchley."

"No", Simons replied. "It's from J.C. Penney."

Pytchley appears to be the preferred riding attire. For boots, Vogel and Dehner are a must. For saddles it's Hermes, and horse sheets, Gucci, of course.

Lynne Lande sat on a lawn chair, reading a horse magazine. She is a horse-show mother. She also does a lot of needlepoint. "I have to keep myself occupied somehow," she said. Lande accompanies her son to about 40 shows each year.

Yes, the traveling gets tiring and expensive, she said, but the sacrifice is well worth it. She rattled off her son's achievements. "It's truly a wonderful sport. It teaches the children maturity, responsibility and poise. It's time and money well spent."

Mark Stello, a construction worker from Pittsburgh, said he works two jobs to send his stepdaughters, 11 and 14, to these shows. He and his wife, a waitress in a small Italian restaurant, take turns traveling with the girls. "Except for big shows like this one," he said. "Then we both come."

The family has had to do without many things, such as a new air conditioner and a new car, to pay for the training, the clothes, the travel. "When we see our little angels gliding on the white horses," he said, "the vacation or the furniture doesn't seem that important anymore."

As the announcer read the winners in the small pony class, the young competitors held their breath. One girl bit her lip so hard it bled. Another muttered repeatedly, "I'm so nervous, I could just die."

The winner was Susan Homa, 13, from Warrington, Pa., and her pony, Peter Rabbit. Homa strolled out of the ring clutching her silver pitcher. There were tears in her eyes. "I'm really excited," she said, her voice shaking. "I'm really proud of Peter. He turned out to be quite a guy."

She got him from the ASPCA. She gave him a big hug for what she said was the best moment of her entire life.

Chapman Sharpe, 11, from Brooklyn, wasn't quite as happy. He finished last in the same category. Two years ago, he said he knew nothing about horses. The boy now spends the summers training in Middleburg, and more than anything else in the world he wants to be a great rider. "The place you come in doesn't matter. It's all for fun," he said, sounding as if he were trying to convince himself.

At the end, the two 10-year-old girls had become friends. They exchanged addresses and planned a slumber party for the next show. "We'll do better there, I bet," said the one with the braids. "And if we don't, winning isn't everything."

"You're right," the other girl said solemnly. "It's the only thing."