Trond Skramstad of Mount St. Mary's came from behind to win the decathlon and UCLA sophomore Jackie Joyner set a collegiate heptathlon record today in the NCAA Track and Field Championships.

Skramstad, a Norwegian, was third behind Mike Ramos of the University of Washington at the start of today's competition. Ramos quickly took the lead from Frank Harrison of Penn and looked like the best bet to win the decathlon. But he could not go the distance.

Skramstad bettered his personal best in the javalin, the ninth event, with a toss of 198 feet 4 inches. Skramstad then won the 10th, and final, event, the 1,500 meters, in 4:26.56 for 7,770 points. Ramos, who led going into the 1,500, finished next to last in that event and dropped to third place, 7,638 points. John Sayre of Southern Illinois finished second, 7,660.

Last weekend, Skramstad, a sophomore at Mount St. Mary's, a small Maryland college, won the decathlon in the NCAA Division II meet in California. The win earned him a berth among contestants from major schools in the Division I championships at Brigham Young University.

Joyner became only the second American to score more than 6,000 points in the heptathlon. She won three of the seven events.