Three steps inside the office building at the Central Moscow Swimming Center, it becomes clear why youngsters here will all but sprout fins to win glory for their country. The room is large and polished, but almost bare except for the incentives necessary to keep the Soviet athletic machine purring.

Those incentives are pictures and numbers. All along the front wall hang poster-sized color portraits of Soviet Olympians, runners and wrestlers in addition to the one of Marina Koshevaya, who at 16 won the 200-meter breaststroke in the Montreal Games.

Anyone walking through the door also cannot miss the reminder of Soviet success in prior Summer Olympics. Their metal count -- gold, silver and bronze -- is tabulated for each of the Games since 1952 and hangs inside a large glass-enclosed frame.

The total is 683 medals: 258 gold, 221 silver and 204 bronze. Although it is not mentioned at this pool, Soviet brochures nearly always add: "It is noteworthy that U.S. athletes won 606 medals, including 254 gold medals, in the same period."

On the opposite wall are two slightly smaller pictures in black and white, of the boy and girl from the pool who made the '76 Soviet Olympic team. To their right are even smaller pictures, 8-by-10s, of the dozen masters of sport currently training at this pool.

If Bowie Kuhn's pitchmen were phrasing it, the party line would be: "Olympic fever -- catch it." Cynics would add: "Or else."

Intimidation hardly is necessary. There are degrees to all serious Soviet sports and appropriate perks for each, ranging from pictures being displayed, and easy access to training facilities and the best coaches, to a life of luxury by standards here.

Gradually and swiftly, a Soviet athlete can move up from third-level, second-level, first-level youngster, third-level, second-level, first-level adult, candidate for master of sport, master of sport international, master of sport, merited master of sport and -- at the summit -- the Order of Lenin. o

"The sports committee pays 1,000 Olympic men and women $5 million annually to spare them the headaches of working for a living." wrote former Moscow screenwriter Quri Brokin in a book called "The Big Red Machine" published in the United States last year.

"A special commission of the sports committee appraises each sport in terms of international prestige and sets cash stipends and rewards. It is speculated that monthly stipends are $250 for volleyball, $350 for gymnastics, $400 for hockey and $500 for superheavyweight lifting.

"The reward for capturing a world championship or beating a world record has ranged from $1,000 to $3,000, and Olympic gold is valued at anywhere from $4,000 to $8,000 per medal."

The Central Moscow Swimming Center is impressive even by Soviet athletic measurements. It began as a mistake. Once an ancient cathedral stood on the site, but Stalin had it torn down. He wanted a Western-like skycraper to take its place. When the first stories began to sink into the mud, though, the only alternative to total embarrassment was to build the world's largest swimming hole.

"There are 50 pools in Moscow and each has a special children's swim school," said Assistant Director Nikolai V. Portnov, rattling off the obligatory number almost by rote for the translator. His office is sparse, with a desk that has four phones -- all red -- a table the size of ones in American school cafeterias and Lenin's large lacquered face looming overhead.

"We have 20 coaches who teach swimming here," he continued. "They work full time, eight hours a day. Six hours are spent teaching. The other two are spent planning. They can work at teaching three hours in the morning and three hours at night if they like. Our pool has lights.

"Our coaches train 10,000 new swimmers each year. There are 300 sportsmen who train here (in a separate, Olympic-sized pool and diving area.)" He was giving the dimensions of the pool and a fact that 55 billion people had swum there in 20 years when his eyes began to twinkle and he offered another fact.

"The 55-billionth person was a 90-year-old man," he said.

The director of another children's sports school had a similar personality. She is a Nina Khruschev figure, a former gymnast who, during a sermon about the glories of Young Pioneer Stadium, patted her ample tummy and arms, laughed and said, "I am not in form. It is the fate of everybody." a

Young Pioneer Stadium can be imposing and pleasant. It is where Rodnina and Zaitsev honed the performance that mined more Soviet gold inpairs skating at Lake Placid. The entrance is through an enormous back gate: the walkway to the gyms and tracks passes trees and a white statue of Lenin in deep thought.

There is a 400-meter cycling stadium with stands that can seat 10,000, an arena for gymnastics and one for figure skating, and a track with an asphalt running area and artificial-turf interior. One of the administration buildings originally was built by local merchants for Nicholas II to use as a bedroom during a visit nearby.

The director, Zinaida Nabalova, explained the routine for young athletes -- usually of ages 4 to 14 -- at these sport schools.

"They come here in the morning" at 8:30, she said. "They stay for an hour and then go to their regular schools for classes. Then they come here in late afternoon, have dinner, go home and do their lessons and then return here for another two hours.

"First-class sportsmen and masters of sport will train for two hours in the morning and three hours in the evening. There also are special schools where the sportsmen train and study at the same place.

"But this school is well named, because there was pioneer work here. It has the first cycle track in Moscow, the first athletic track and the first roofed skating rink. They (Rodnina and Zaitsey) are Central Army, with two rinks to train on. But they prefer this one."

Although they probably do not know each other, the pair of Portnov and Nabalova skated mechanically through separate interviews miles apart. Portnov is a narrow-faced man, with hair almost totally gray but the look of a once-fine athlete. He was the national swimming coach before the '72 Olympics.

"No one from this pool made the Olympic team this year," he said, "but we have two on the national team and four candidates (who did not make it).

"Children up to 14 are prepared here. Then they are transferred to preparing centers. The most talented are accepted to the national team."

And what happens at these preparing centers?

Perhaps the translation suddenly became fuzzy. Or perhaps his response revealed the essential tone of Soviet life, that in sport or government or business, few officials are given either more information or authority than absolutely necessary, rather like assistant coaches under certain U.S. football tyrants.

Portnov had a catchism-like white book he referred to during the interview. But when he was asked about Soviet athletic life at the next level, he shut the book and said, "You'll have to ask someone on the Moscow Sports Commission."