IT WILL PROBABLY COME AS no great shock to any living American that one of the first things gymnast Missy Marlowe did upon returning home in triumph from the 1988 Seoul Olympics was walk into a Wendy's and order a cheeseburger and fries.

She'd had one dream come true in Korea - competing for the U. S. Olympic Team in the Games of the 24th Olympiad - and now she was realizing another one.It had been eight years since she'd walked into a restaurant and ordered anything she wanted, and since she was all of 17 that amounted to practically half of her lifetime.

Ever since she was nine years old she had dedicated herself to being a world-class gymnast. Twenty-five hours of training a week, week-in, week-out, along with a strict diet, a strict schoolwork routine, a strict sleeping schedule, and, by necessity, a sharply curtailed social life.

She made it to the top of the mountain all right. She'd have come home from Seoul with a bronze medal if East Germany had only had better timing with its revolution. As it was she came home a conquering champion, an Olympian, a legend in her own prime.

She was also burned out on gymnastics.

"I didn't even want to say the word," she remembers.

She did want to say "cheeseburger," and "dates," and "parties," and "free time."

"I thought I'd missed so much," says Missy. "For about two months after I got home from Korea I did everything I'd promised myself I'd do. I rebelled. It was great . . . well, it was great for a while."

Utah's most famous gymnast soon made a striking discovery. She missed the discipline. She missed the dedication. She missed gymnastics, of all things.

And she missed the direction gymnastics had given her life.

"I'd gone from wanting everything," she says, "to not knowing what I wanted. It was hard to deal with."

Harder yet was dealing with the abrupt end of her participation in world-class gymnastics, a sport that favors the young and the lithe and those who dedicate their life to the sport.

It was time now to move on, but where do you go from the Olympics? Missy went to the University of Utah.

She joined Coach Greg Marsden's gymnastics team for the 1988-89 season, only months after the end of the Olympic Games. That was a year ago. It seemed like a good idea at the time. Only it wasn't. The culture shock was considerable.

"I wanted to be involved in gymnastics, but I was still burned out," says Missy. "I wasn't 100 percent - and I was heavier than I'd been."

She was as close to being a basket case as is possible for a 17-year-old phenom has-been to be a basket case.

"Emotionally, it was really hard," she says. "I scared them all."

By that, she means she scared Marsden and his coaching staff, and Dr. Keith Henschen, the Utes' team psychologist, who, eventually, talked Missy in off the ledge between Olympian and college student.

"He made all the difference in the world," she now says of Dr. Henschen.

It should be pointed out that during Missy Marlowe's winter of discontent she nonetheless qualified as an All-American in two events - the beam and uneven bars - and placed fourth for Utah in the national meet in both events. Such are the spoils of half-a-lifetime of dedication. On her worst days she was better than most contestants.

But now that she's much more comfortably settled in her post-Olympic life, she's back to normal, which is to say rather sensational. In her second season as a Ute she's already posted school records in the all-around, the beam and the uneven bars. She'll be the favorite in all these events at this weekend's HCAC meet in the Huntsman Center, and she could very possibly wind up as the top collegiate gymnast in America by the time the nationals come and go a month from now in Corvallis, Ore.

Missy recognizes these meets aren't the Olympic Games. That hasn't lessened her enthusiasm. If anything, it's increased it. "I look forward to the college meets," she says. "I used to get so nervous. I had strep throat before every competition I was so nervous."

"I know I'm not as good of a gymnast physically as I once was," she says. "It's a young person's sport. But mentally I'm 10 times better."

For additional motivation, she has her hometown school's reputation as a dictator to be concerned about.

When she was a developing gymnast the Utes were always winning national championships. They won six straight from 1981 to 1986. But last year the Utes were fifth, and they were second the two years before that. It's been three years since they won it all. A drought, by Greg Marsden standards.

"I followed every one of those six championship teams," Missy says. "Those gymnasts were my heroes. I feel this is the best program in the country. To get Utah back on top is a major priority."

This season, the Utes are again ranked No. 1 in the country.

"You know," says Marsden, "what I really respect about Missy is that what she went through (after the Olympics) was a sincere struggle; this wasn't a bad kid checking out, this was someone facing a difficult change in her life. She easily could have gotten out of the sport and said, `I'm an Olympian, world, you owe me now.' But she didn't. She didn't dodge anything. I applaud Missy for not resting on her laurels. She's a competitor, there's no question about it. She comes through when she has to."