Having learned from the West that athletics and commercialism can be easily combined, the Soviet Union described elaborate plans yesterday to market a formerly all-Russian sports event to the world in 1979.

In effect, the Soviets who will host the 1980 Summer Olympic Games, are piggybacking a second event onto those games and billing it as a pre-Olympics that will use the same facilities as the Olympics.

The Spartakiade, as the 1979 games are called, will mark the first time the Soviet Union has permitted foreign advertisers to put up signs in Russian stadiums and Russian streets.

In a prelude to the advertising that will accompany the Olympics, foreign businesses are being invited to advertise their products on billboards for the 16 days of the Spartakiade.

Lothar Bock, the West German entrepreneur who negotiated the sale of North American television rights to the 1980 Olympics to NBC for $85 million, has been asked by Soviet authorities to sell the Spartakiade abroad.

Bock told a press conference yesterday the games promise to forge new commercial relationships between the Soviets and other nations.

In addition to advertising space in Moscow during the games, Bock has for sale commercial time during the 16 days of five-hour-a-day television contemplated for the Spartakiade and the TV rights around the world.

Bock offered the American rights to NBC first because it bought the Olympics, but he said the network turned them down because they are televising the Pan American Games, which begin five days after the Spartakiade closes.

"I believe it will be on U.S. television," Bock said. "One beauty of this country is you have so many opportunities" to sell TV rights. Bock said he is about to approach ABC and CBS.

The Soviet Union has held a Spartakiade every four years in the year before the Olympics since 1958, but 1979 will be the first time foreign athletes will be invited.

Victor A. Ivonin said that about one-fifth of the 10,000 Spartakiade participants will be foreigners, with no more than one athlete or team from any single foreign country participating in any event. In the Olympics, a nation can enter three athletes in each event.

Ivonin, deputy chairman of the soviet Committee for Physical Culture and Sport, said invitations would be extended through the sports bodies of foreign countries and would be guided by Moscow's desire to have participants from all parts of the world and its desire to have the world's best athletes.

All Olympic events plus chess, tennis, sambo wrestling and modern rhythmic gymnastics will be contested.

The July 1979 event is actually the finals of a nationwide competition. The last Spartakiade in 1975, involved 40 million athletes who competed at local levels in a series of eliminations before the final 7,000 reached the finals.

South African and Rhodesian athletes will not be invited because they are not members of the International Olympic Committee, Ivonin said. He refused to answer directly whether athletes from Israel, China, or other nations with which the Soviet Union is not on friendly terms, will be invited, but indicated they would not unless they had an athlete of unchallengeable superiority in his event.