RALEIGH, N.C., July 12— Anyone interested in knowing what some of our younger choreographers are up to would have found a visit yesterday to the American Dance Festival instructive.

All last week there were concerts featuring works of five choreographers representative of what the festival terms modern dance's ''emerging generation.'' But yesterday was a real marathon with a concert in the morning, two in the afternoon and one at night. After all that dancing one's eyes might have been dazzled and one's brain might have been boggled. But one would have gone away enlightened.

Still another aspect of scheduling made the ''emerging generation'' programs unusual. Although festival events are ordinarily held on the Duke University campus in Durham, these performances took place in the Stewart Theater of North Carolina State University as part of an effort to make the festival serve a whole region.

Chosen from 50 applicants, the five choreographers were Johanna Boyce, Molissa Fenley, Bill T. Jones, Charles Moulton and Marleen Pennison. In addition to presenting older works, each offered a striking new piece commissioned by the festival.

The preparers suggested that the young choreographers drew upon the accomplishments of the last two decades of dance experimentation. Yet these choreographers are also using the compositional approaches that they have inherited in their own personal ways.

Two decades ago choreographers began experimenting with all kinds of movement, including so-called non-dance movement. Regarding movement as a thing in itself, they abandoned dramatic pretexts. And wishing to avoid making dance a cult of personality, they disdained virtuosity. The resultant dances tended to be sturdy and invigorting.

Whereas the preceding generation stripped dance down to its essentials, yesterday's choreographers appeared to be adorning the art, for their works revealed a concern for both drama and virtuosity.

The most emotionally explosive premiere was Mr. Jones's four-part ''Social Intercourse.'' Yet anyone who heard only a few measures of the instrumental portions of Joe Hannan's score and saw only a few minutes of the repetitive choreography might have concluded that it was a study of pattern for pattern's sake.

However, the vocal portions of the score included commands, patriotic cliches and excerpts from courtroom proceedings concerning the assassination of the Rev. Dr. Martin Luther King Jr. The choreography was always harsh and insistent and the way the finale became a tremendous crescendo of rage made ''Social Intercourse'' an evocation of the frustration and anxieties of black Americans. The dancers were compelling and the musicians, conducted by the composer, were nothing short of superb.

Highway noises dominated the sound collage that Phil Lee devised for Miss Pennison's ''Free Way,'' a vignette about teen-age boys who hang around gas stations dreaming of cars and girls. Eventually, some of the boys got married, some split up with their wives but all retained their love for cars.

Although older choreographers might well have treated such a theme, they might not have treated it as Miss Pennison did, for she was choreographically eclectic in her choice of movement. There was much realistic nondance gesture. Yet an auto race was indicated by virtuosic runs and turns. For Miss Pennison, the important thing was not whether her movements fitted conventional definitions of dance, but whether they were dramatically appropriate.

Some young choreographers who are fascinated by virtuosity but who do not wish to immitate either classical ballet or the established techniques of modern dance have borrowed skilled rough-and-tumble movements from sports. Thus Mr. Moulton has created several dances based upon the ways that balls can be passed from person to person.

''Expanded Ball Passing,'' to an electronically modified percussion score by A. Leroy, continued these explorations. But in addition to bounding and tossing balls, the dancers sprinted and dashed about in what could have been fantastic games of tag. Whereas, previously, ball-passing was the subject of Mr. Moulton's dances, he here made the act of ball passing a part of his dance technique that he could use just as another choreographer might use turns or leaps.

For Miss Fenley's ''Gentle Desire,'' Mark Freedman composed an electronic score that went lickety-split. The two-part dance, in which a trio was followed by a solo, also went lickety-split. Filled with bewildering array of shrugs and shakes and whirls and jumps, the dance was not only fast, it also looked awesomely unstompable.

That choreographers are experimenting with space as well as movement was evident from Miss Boyce's ''Waterbodies'' which was presented not in the theater, but in a nearby swimming pool. Miss Boyce, who loves to work with nondancers, on this occasion set a cast of nine splashing and paddling about the pool to rippling harp music by Jack Eric Williams, and from time to time films by John Schabel showed them moving underwater.

As Miss Boyce's dances on land have done in the past, this aquatic piece presented ordinary people at their attractive best. Because they all appeared to be good friends, we in the audience started wishing we could be their friends, too. For that matter, all of the concerts yesterday did much to win friends for experimental modern dance.