Team of middle-aged rowers may stroke its way to the Olympics

It's a long way from a bathtub regatta to Olympic-class rowing. But by their own calculation, the ''Dirty Dozen'' think they're nearly there. Granted, their calculations don't always add up:

* The Dirty Dozen are a crew of 10, not 12.

* Rowing has a reputation for being a youth-oriented sport, yet the average age of the Dirty Dozen could best be described as ''middle.''

* Olympic oarsmen have usually rowed 10 years, but the Dirty Dozen first dipped their oars in a bathtub-regatta fund-raiser just 16 months ago.

Yet, against all odds and to the amazement of the rowing world, this group of Bay Area businessmen is entered in the Olympic trials this spring. And the group , led by a 59-year-old real estate executive, has a fair shot at making it to the finals, says Julian Wolf, chairman of the United States Men's Olympic Rowing Committee and team manager for the US Olympic rowing team.

The story of the roguish rowers has equal parts of American dream and Californian insouciance. What sounds like a half-baked, Walter Mitty daydream has sparked the imagination of a community and 10 grown professional men who are sacrificing work for workouts.

The promise of the team even lured Allen Rosenberg, a New York State administrative law judge, from his job to coach the Dirty Dozen in California. It's also a bit of nostalgia for Mr. Rosenberg, who coached the only US oarsmen in recent memory to win an Olympic gold medal (Tokyo, 1964).

Meanwhile, US rowing officials say the Dirty Dozen are a public-relations coup for the sport with a reputation for being a clubbish, Ivy League activity for young men. ''It shows you don't have to be a bull 18-year-old to get started ,'' Mr. Wolf says.

Having played local softball and rugby together, the men's fraternizing spilled over to a bathtub regatta where a UC California Berkeley rower noticed they were pulling a remarkable 38 strokes a minute. That was all it took to encourage the sports enthusiasts. Leader Allen Trant, a 59-year-old executive with Consolidated Capital Realty Investments, went directly to Julian Wolf to learn what it would take to make it to the 1984 Olympics.

''When I first met Allen Trant a year ago, I told him, in all honesty, 'Don't go through with this. You have less than a zero chance.' But I didn't know who I was dealing with,'' says Wolf, who calls them ''an over-the-hill mob.'' He adds that he watched the group place respectably in the Canadian Henley and the Head of the Charles in Boston, but that their skills were not refined.

The group continued to spend lunch hours stroking determinedly up and down the thin strip of the Oakland estuary, however. They take an additional two hours every day away from their jobs in the mortgage business, real estate, education, sales, and carpentry to lift weights and run the 72 steps of the UC Berkeley stadium. In the bright sun of a 70-degree winter day here, they look as fit as any Olympic athlete - not a hint of paunch and arms bulging in the relentless pull-and-glide, pull-and-glide.

With a closer look, the experience of age shows around their eyes. But that's why their efforts are so inspiring, Wolf says. ''It's the old American dream that at least they have the opportunity to try, and the notion of youth vs. middle age.

''If you look at it logically, no, they don't have a chance. But,'' he adds, ''they will make it past the first heats (at the trials). And even knowing the caliber of competition, in my opinion they'll probably make it to the finals.''

Coach Rosenberg sees the Dirty Dozen as some fine raw material to work with. ''They're a long shot, so it's an enormous challenge for me to try to condense the training normally required in thousands of miles of rowing so that they can acquire the skills (in a couple of months). But they're enormously competitive guys.''

Their collective competitive imaginations keep them on an unbroken training schedule. And they focus on the process rather than the result, Mr. Trant says. ''Personally, I want to be able to say I attempted it. We have a total commitment with the idea of being in the tryouts for the Olympics, and the No. 1 thing is the effort of trying.''

The only rowing events open to trials are the four-man with coxswain, pairs, and pairs with coxswain. The eight-man and four-man without coxswain are selected at camp by US Olympic coaches. So it's agreed the Dirty Dozen have a chance only in the four and pair categories.

It's not certain which members of the team will actually man the shell. The sport is much like a ballet, where timing and balance is as important as strength. So the youngest and strongest of the Dirty Dozen won't necessarily be the ones who actually enter the trials.

There's no way to measure the Dirty Dozen's chances in terms of speed. Though all races are 2,000 meters, no world records are kept because of variables such as current, depth and temperature of water, and wind.