Frequently, when an athlete skyrockets to fame, he finds the ensuing attention and adulation suffocating. Especially when he is a self-described loner.

"Most of the time I like being by myself," Billy Sims said. "I used to spend about 90 percent of my time alone. I haven't done that for a while, though."

Sims laughed, something he does frequently. Since winning the Heisman Trophy a year ago, his life has been a nonstop whirl of interviews, speaking engagements and requests for his time.

"I knew there would be a lot of attention but I never knew it would be like this," he said. "It started right after I won the Heisman and it hasn't let up at all."

Sitting in a lounge of the OU Student Union, the most important game of the year, against Nebraska, only 24 hours away (WJLA-TV-7 12:50 p.m.), Sims was relaxed. The student union was empty because of the Thanksgiving recess, so Sims, baseball cap tugged over his large afro, didn't have to raise his soft baritone voice to be heard.

He was talking about the Heisman, what it meant to him last year, what it means to him this year and how his perspective on what it means for the future has changed during the last 12 months.

"I remember when they told me I had won last year it was like my heart just stopped for a minute. I couldn't believe he was talking to me.

"I had thought I had a chance but, really, I just expected to be up there high in the voting. But when I did win, I was very happy."

Sims doesn't expect to win this year, either. "I think Charles White (of Southern California) will get it," he said. "He leads the country in rushing. That's okay with me, though. I've still won the Heisman and I'm proud of that. Charles' winning it won't change any of that.

"And you know what they say in the pros: They don't buy Heismans. You can't eat them, either."

Sims laughed again. He has an engaging sense of humor. He can and will laugh at himself; he does not take himself seriously the way many heralded athletes do.

"I like football, I like getting away from guys when they try to tackle me.

But I don't eat, drink and sleep football. I know guys who do and I feel sorry for them."

Friends say that Sims would be as happy making a living as an auto mechanic as playing pro football. "He plays the game because he's good at it," said Oklahoma halfback David Overstreet, Sims' best friend. "He doesn't go wild over it like a lot of people do."

Some in this football-crazed state find Sims' casual attitude toward the game and his future in it rather strange. Others find it impressive.

"I've thought a lot about pro football because I know it's a good way to get off to a good start financially, a way to make some money while I'm still young," Sims said, stroking his neatly trimmed goatee. "But I don't look at football as a be-all and end-all."

"I get a lot of attention right now because I play football. But if I get hurt tomorrow, who's going to be around? It can be over in a hurry."

Because he realizes that, Sims is about to become a wealthy young man, Sooner Coach Switzer has pulled him from games when they are safely in hand. As a result, Sims has carried the ball only 196 times (for 1,259 yards and 22 touchdowns), compared with 258 carries for USC's White.

"Billy is a million dollars walking around right now. Why risk his body any more than necessary?" Switzer said. "He's a special kind of back. I wouldn't want to do anything to keep him from getting his full shot at the pros."

Switzer has had several great backs in his seven years at Oklahoma -- Greg Pruitt, Joe Washington, Horace Ivory and Elvis Peacock, among them. But he says Sims stands apart from the others.

"This guy's a man," Switzer said. "I mean he's got the size and the strength (Sims is 5-11 1/2, 210 pounds and can bench-press 350 pounds) to run over people when he's not running around them.

"Billy has that innate ability every truly great back has: He makes people miss him. You'll never see anybody really hit Billy Sims a solid shot."

Sims admits that the possibility of injury has concerned him this season, that he has been delighted when Switzer has pulled from routs early and that occasionally the thought that he should be in the pros now crosses his mind.

Sims is 24, three years older than most of college seniors. He lost a year of school as a boy because he moved frequently between his native St. Louis and Hooks, Tex., the town of 2,556 where Sims says he and his wife of five months, Brenda, eventually will settle.

"Sure, I think I should be in the pros sometime, because I think I'm pro material," he said without a trace of arrogance. "But I thought about being in the pros last year during the season. I don't really care who drafts me as long as it's a good organization. I just want to play for a few years and then go back to Hooks."

"Billy likes things quiet," Overstreet said. "You'll never catch him looking for attention or the limelight. Of course, he doesn't have to look for attention, it comes to him."

That attention was a long time coming. His first three years at Oklahoma, Sims struggled. He played little as a freshman, was injured and red-shirted as a sophomore, then hurt an ankle in 1977 while leading Oklahoma to a nationally televised win over Ohio State.

Last year, it finally came together. "I was beginning to wonder," he said with a wry grin, "if I was ever going to make it. I thought football and me might be through. But it finally got better."

Sims' awesome statistics -- 1,762 yards in 231 carries for an amazing 7.6-yard-per-carry average -- overcame the lack of publicity as he edged Penn State quarterback Chuck Fusina for the Heisman, becoming the sixth junior in 44 years to win.

"I'm proud of what I've done this year because I know it was going to be harder. We don't have the experience we had a year ago. We're still coming together. But I've done all right."

He has done all right off the field, too. This spring, Sims will graduate with a degree in recreational therapy. He hopes to use it to work with retarded children, like his 16-year-old brother.

"I know when I leave here someone else will come along and be the star because that's the way it is around here," Sims said. "But I've enjoyed this year, the people I've met, the places I've traveled. I'm glad I did it.

"But I'll be just as happy when I'm back home in Hooks. I'll like being able to take things easy, work on my own cars. I've worked hard to get to where I am. I think I've earned a good career. At least I hope so.

"But going home is great. It's quiet there. That's what I like best: quiet."

Sims smiled at the contradiction between his current life style and his ideal. "I haven't had much quiet the last year. But that's okay. It all comes together eventually. It did in football. I'm sure it will with the rest of my life."

Saturday's winner between Oklahoma and Nebraska will take the Big Eight championship and earn a trip to the Orange Bowl to play undefeated Florida State.

The Sooners (9-1) are rated slight favorites in spite of Nebraska's record (10-0) and higher ranking -- No. 3, Oklahoma No. 8.

Both teams are hobbling slightly. Oklahoma will be without all-conference safety Darrell Ray, considered be many to be the Big Eight's best defensive back. Also doubtful is defensive tackle John Goodman.

For Nebraska, leading rusher Jarvis Redwine, hobbled for two weeks by a knee bruise, has been limping on an ankle injury suffered in the fourth play of last week's 34-3 rout of Iowa State. Redwine has only practiced one day this week and may not start. The Cornhuskers have the luxury, however, of having I. M. Hipp, a 1,000-yard rusher in both 1977 and 1978, back from a toe injury and ready to play.

This is a matchup of statistical giants. Nebraska leads the nation in rushing offense, is tied for second with Oklahoma -- in scoring offense (36.5 points a game), is second in total offense and first in rushing defense (67.5 yards a game).

Oklahoma is second in scoring, third in rushing and Sims is first in touchdowns with 22. Between them, the two teams placed 14 men on the All-Big Eight first team.

Elsewhere, Arkansas will try to clinch a Cotton Bowl berth against the Oklahoma-Nebraska loser by bearing SMU. Texas, which will go to the Sugar Bowl if Arkansas wins, will play Baylor, and Southern California will attempt to clinch a Rose Bowl date with Ohio State by beating UCLA. If the Trojans lose, Washington goes to Pasadena.