In his reckless heyday, Larry Brown caused his fans as much anxiety as pleasure. What would become of the Redskin halfback who used his body as though it were a rental?

Perhaps other players had nearly equal desire, but only Brown-with his acrobatics, tolerance for pain and plain stubbornness-seemed willing to die for a first down.

After every Brown somersault into the end zone, Redskin fans asked themselves, "Will he get up?" In his final three years, Brown ran through the NFL's predators like a wild animal with a broken leg. He was pathos in cleats.

Washington's worries over Brown did not end with his last game. Could a man who played football with his whole soul possibly find a second life after football that would make him happy?

Brown was born in a Pittsbrugh ghetto, almost deaf in one ear, and exucated at Dodge City Junior College and Kansas State. When football, for him, ended in Carlisle in the summer of 1977, it appeared he would have problems finding a second arena for his unusual talents.

Those who thought Brown lived only for third and short yardage have now been proved wrong.

Few great athletes have made as quick, complete and startling a break with their former lives as Brown.

Only 17 months after retiring, he has transformed himself from Redskin running back in E. F. Hutton account executive. When Larry Brown talks, people listen.

"This is a tough business, and a total change for me," said Brown this week, sitting in a leather chair in his three-piece suit. "But then, whenever people tell me that I can't do something, that's just what I want to do."

Around Brown's desk are the perplexing tickertapes and flip-flopping stock-quotation boards of a major brokerage house.

Brown has deliberately, and with almost a decade's premeditation, chosen to switch from the ultimate young man's field of combat-the gridiron-to the ultimate adult's war zone-big business.

"In some sense, I'm a rookie again," said Brown, not with fear in his voice but with exhilaration.

If, instead of graduating from teen-age switch-blades and NFL concussions, Brown ahd graduated from Harvard Business School, he qould be right on scheldule now.,tAnyone looking for a 31-year-old Washingtonain of business expertise, social conscience and connections should just step into Brown's office.

"Since I retired, I've never looked back. No one ever won a race looking over his shoulder," said Brown.

"For eight years, I was like an actor on a stage. But when you step down off that stage, you better not take that stage personality into the audience."

Even during his glamor years, Brown was rigorously annlyzing his limitations and preparing to join that audience.

When he led the NFL in rushing in 1970, he was finishing an undergraduate degree in the offseason. As NFL Player of the Year in 1972, he was also studying economics and marketing at Maryland.

While his knees deteriorated, Brown's mind grew. He worked as amny a seight hours a day with a tutor to pass the New York Stock Exchange exam.

"I've never wanted easy things," said Brown. "People who give you things can take them away very fast. But if you earn something yourself, usually the only way you lose it is if you blow it yourself.

"I'm a person who has to learn by repetition, learn by mistakes. I've always had to take my bumps and bruises in everything. I learned the hard way that restaurants weren't my business. I didn't have the time when I was playing to run Larry Brown's Restaurant properly. If it's got your name on it, you should understand every facet of the business from the floor-scrubbing on up.

"If you lose a game, if you lose money in business, you should at least know why . . . that's the only way you can come out of it with something."

For Brown, everything has come just as hard as his blind, spraddle-legged leaps into chaos on a football field.

"The business deals an athlete is offered are generally no good. In fact, they're usually rotten," said Brown.

"I didn't want to fall for that instant-success gimmick. I want a solid foundation."

Consequently, Brown sought out a job that matches his cautious meticulous, workaholic instincts. His current specialty is "personal financial management." That's a euphemism for recommending a total money plan for people with six-figure incomes.

"I don't try to supplant a client's current counselors-his lawyer, accountant, agent, insurance man and whatnot. We try to get everyone together in a round-table discussion and put everything into one coordinated plan."

It is not hard to dicover why this work has a deep hold on Brown. It has little to do with dollars.

"I've always believed in selling yourself on performance, not talk. I like concrete things. I always knew that somewhere down the line in this job you wouldn't be able to fake it anymore than you could fake it carrying the ball.

"My business now has no end zones, no halftime shows. But emotionally it's the same. When someone puts $250,000 of their money in your hands to manage, you're elated. That's the final proof of confidence in you.

"That's not somebody asking, 'Hey, Larry, who's gonna win Sunday?' or 'do you have any tickets?'"

Many athletes have a loathing of being judged or befriended on the basis of past glories. Brown is an extreme case. His whole attention is on the present.

He senses that in a game where the intricate rules have names like "estate taxes," "pension funds" and "profit sharing," his doggedness will off.

"When they change the rules on the tax consequences of term insurance, nobody tells you," said Brown, grinning. "The guy who finds out for himself has an edge."

Nevertheless, Brown is not totally concerned with what he calls "The Cool Hand Luk-type atmosphere in this business where all the forms of intimidation are subtle."

It is hard to find a charity or community service group that Brown has not worked with. It is like pulling teeth to get him to name them, but he runs out of fingers keeping track.

However, he is careful to say, "Now I'm just the local cochairperson of this NAACP fund-raising drive. I don't want people to think I'm doing more than I am."

But, whether the cause is crippled children, Special Olympics, a clothathon, POW%@S-AND-MIAs or the hard of hearing, Brown is usually doing more than he says.

"People are just basically interesting," he explained. "Yes, I've gotten to know extremely wealthy people and famous people. But I have just as many frineds who are jsut walking the streets.

"I've always thought that lift was like a puzzle and that you try to get a look at as many different pieces of that puzzle as you can. The more you learn, the more kinds of people you know, the more pieces you have and the bigger picture you see.

"At every stage of my life, I've had the feeling that all of a sudden, someone raised a shade and I could see more than I did before . . . things begin to open up to you.

"For instance, because of the business experience I've gotten, I feel like I can walk through a city and understand it better.

"You can imagine the sorts of financing that cause a block of houses to be built in a certain place or in a certain way," he said.

Then Brown stands up and strectches his knees, which still ache if he sits still for long.

'When you're young, you live' . . . eh . . . what's that word? Not latitude' . . . yes, 'vertical.' Yu live vertically . . . in terms of success.

"But when you have had some success, you have to decide whether you are going to keep going up, or if it is more important to start broadening out . . . start moving horizontally.

"If you continue to think vertically, you'll be more apt to walk over people. On the other hand, if you branch out, you'll live on a sort of elevated plateau where you keep learning more abut many things."

Brown smooths out the creases in his pants and sits back down, laughing at himself a bit for getting carried away and talking with his hands-drawing vertical lines and elevated planes, and pretty much making it up and enjoying it as he goes along.

"I remember the first time (former Redskin) Pat Fischer brought me into a stock brokerage," said Brown, focusing on specifics. "You might say I was terribly confused about his working environment. Even the ticker tape machine scared me.

"I still remember how happy I was the first day I was able to read that darn tape."

Now that tickertapes-as well as stocks bonds and annuities-no longer seem alien to him, it might be expected that Brown would be hitting on his old friends for business.

"That might have been part of the original idea." said Brown, "but I've found that all my clients are doctors, lawyers, professional people . . .not a single athlete.

cSometimes an old teammate will see me and say, 'Why don't you come around the locker room and talk'?"

But that isn't Brown's style. In fact, he hasn't been to a Redskin game this year, not wanting to be mistaken for one of the breed of former players turned agent that many pros now see as 10 percent vultures. "Negotiators (agents) tend to be into the business and out of the business very quickly," he said pointedly.

Instead, Brown waits patiently for his hard-won slow-but-steady reputationto bring hims clients.

"I've always tended to be curious about the quiet individual," he said. "On a football field, you always have to look out for the quiet men."

Away from his job, his community work and his friends, Brown quickly becomes one of those quiet men. A bachelor, he lives alone in large house in Potomac, which he jokingly describes as "suburban on the outside, latent ghetto on the inside."

Although he has only propped his feet up in his den and watched "three or four games on TV this year," Brown still wool-gathers occasionally, imagining a crack of daylight between guard and tackle on one of his favorite quick hitters.

No. 43 always liked a muddy field, a snowy and sloppy day like the one at RFK Stadium five years ago Saturday when he had his last great afternoon-running and receiving for 255 yards and four touchdowns against Philadelphia.

Mercifully, those reveries evaporate quickly. "Nature speaks to you in funny ways," said Brown, concealing his smile as usual, except at the very edges of his mouth. "Every time I walk past a little kid throwing a football, my knees start to hurt.

"I feel like I'm a long way from football," he said. "And that's where I should be. Who likes to dwell in the past?"

"What's important," he said, "is that when you leave the game, you still bring the inner things with you." CAPTION: Picture 1 and 2, Redskin great Larry Brown exchanged burgundy and gold for businessmen's brown in the summer of 1977. Brown is now an account executive for a brokerage firm. Photos by Richard Darcey-The Washington Post