WATCH their feet. In a few days, about 7,000 marathoners will stagger over the Prudential Center finish line. Look at the company names bobbing up and down on their shoes or emblazoned on their jerseys.
New Balance, Converse, and Saucony (Hyde) will be well represented. If you thought the New England shoe industry was on its last legs, look no further than Monday's race to refute that cliche.
Each of these Massachusetts firms is an athletic-shoe manufacturer. Each has a history stretching back to the turn of the century. And all three are thriving today.
* Converse, based in Wilmington, reports running-shoe sales in 1983 are up 90 percent over 1982.
* Hyde Athletic Industries, in Cambridge, reports total footwear sales were up 22 percent over last year. ''The sales increases have been due primarily to our Saucony (running shoe) brand,'' says vice-president John Fisher.
* New Balance, in Allston, is a private company and doesn't reveal sales figures. But the company is operating five plants in New England and turning out 12,000 pairs a day, says Ken Akey, a plant foreman.
All three companies had shoes that ranked in the top 20 of the latest quarterly shoe survey by Runner's World magazine.
To be sure, competition is toe-to-toe and the athletic-shoe industry has been roughed up in the scuffle. Both Hyde and Converse have closed factories and now import some ready-to-wear shoes.
For the last 15 years, imports have walked all over the domestic athletic-shoe industry. Since import restrictions were relaxed in 1968 and again in '81, the market has been flooded by Asian-made products. Imports now account for 65 percent of the total US shoe market, according to the Footwear Industry Association.
This blitz was softened somewhat by a burgeoning athletic-shoe market. Thanks to the tennis, running, and exercise booms, more sneakers are sold today than in any other footwear category.
But these New England companies no longer make an ordinary ''sneaker.'' They cringe at the word. The low end of the footwear market is now the stomping ground of imports. To stay alive, US manufacturers have shifted to the higher-priced, ''high-tech'' shoe.
One sign of the new focus is Converse's Biomechanics Lab just a few miles from its Wilmington headquarters (where, by the way, the latest in desk-top decor includes multicolored basketball shoes used as pencil holders).
At the lab, along one wall is a bank of steel and hydraulic Tinkertoy-like machines: a penetrometer, a traction tester, a flexibility station. Open boxes of decimated competitor shoes are stacked haphazardly in the middle of the room. At one end a treadmill is surrounded by microcomputers, lights, and a high-speed camera.
Here four ''shoe scientists'' analyze the physical stresses of running to help produce the ultimate in cross-country comfort. As a competitor put it: ''Running shoes are no longer just running shoes. You have shoes for heavy runners, light runners, short- and long-distance, training and racing, and so on.''
The first company to market an innovative design can capture the heart and soles - not to mention the pocketbook - of the avid running populace. Most shoes sport a price tag of $45 to $100. New Balance has a $130 shoe coming on the market this summer.
Converse, the nation's largest athletic footwear manufacturer, is a latecomer to the serious running-shoe market. It was slow to adjust to the import influx and took its lumps. Since 1976, about 5,000 workers lost their jobs as five New England factories shut down. But the Converse comeback has been ''dramatic,'' says Mary C. Farrell, a stock analyst at Paine Webber.
''Although Converse is playing catch-up, they're playing aggressively - and successfully,'' notes Ms. Farrell.
Says company president John P. O'Neil: ''We're healthy and strong now because we've grown so rapidly (in the last few years). But the growth has come from imports.'' Most of the imports are running shoes from Taiwan and Korea. Converse has only one plant left in New England, which produces injection-molded soles. Other types of Converse shoes are made in North Carolina and Puerto Rico.
By contrast, Hyde makes most of its popular Saucony running-shoe line at its factory in Bangor, Maine. But since 1980, the rest of its athletic footwear has been made overseas.
Before the shift to importing, ''We were making 2,000 or 3,000 pairs a day here,'' says Carmin Sganga, standing next to an aging Singer sewing machine at Hyde's headquarters in Cambridge. Now Mr. Sganga supervises the small basement factory used for research and development and custom-made shoes that go to the firm's paid athlete-advisers.
Hyde looks like a 78-year-old shoe company could be expected to look. The faded and dirty wood-paneled lobby is small. Two dusty portraits of bespectacled Hyde family presidents peer down at the hustle and bustle. But next January the headquarters will be moved to a new $3 million building in Peabody, Mass.
The Saucony shoe didn't become a star overnight. Success came slowly. ''We didn't have the funds for promotion. Nike was giving away more shoes than we used to sell. On the way up, it was just word of mouth,'' says vice-president Fisher.
In a way, Hyde's initially less-than-blistering sales pace has been a blessing. Retailers watch quality as a shoe becomes popular. The Saucony footwear has remained consistently good, according to Duke Hutchinson, manager of Marathon Sports in Cambridge.
''Saucony makes good stuff. It's an example of a company growing at a reasonable rate - unlike New Balance,'' Mr. Hutchinson says. ''New Balance went bananas. They grew too fast and tried to be all things to all people.''
At Bill Rodgers's Running Center, manager Charlie Rodgers agrees: ''New Balance was nominated by Runner's World (in 1976) as the best shoe. They increased production and quality went down the drain.''
That's past history, reply New Balance officials.
From his newly renovated bare-brick office above the factory, marketing manager Bruce Goral points to the findings of Sporting Goods Business magazine. ''The Feburary issue shows New Balance ranked first in terms of quality by 26 percent of the retailers surveyed.''
Indeed, in the noisy factory two floors below, Ken Akey says the number of quality check points has increased. ''Every department has a quality check now, '' shouts the plant manager, pointing to the different work stations.
In the effort to produce better quality faster, New Balance has put a little high-tech into the production line. With a bit of prodding, Mr. Akey shows visitors the new computerized sewing machines. But he won't say much about them. They're producing a consistent pattern that ''has everybody in the business wondering how we do it,'' he says.
The entire Allston factory is running at peak capacity. Beneath bunches of shoe uppers, hanging from the ceiling like bananas, 158 workers (mostly Greek and Portuguese immigrants) glue, grind, pound, and stitch 3,000 pairs a week.
Along with running shoes, this factory is making women's aerobic shoes. At the other Massachusetts and Maine factories, New Balance now makes basketball, tennis, boating, and hiking shoes.
In fact, each of these three companies is diversifying to cash in on all the facets of the fitness boom. Hyde recently brought out a line of ''Davis Cup'' tennis shoes under its Spot-bilt brand. New Balance has been doing exceptionally well selling logo apparel. Converse, which dominates the basketball-shoe market, will introduce two new running shoes this summer and hopes to parlay its official Olympic Games sponsorship into increased market share. The company has exclusive footwear advertising rights on ABC and plans to spend $3.5 million over the Games' two-week span.
''The competition is fierce,'' says John O'Neil of Converse. He warns that without import restrictions (which would, incidentally, hit the running-shoe market-leader Nike) there will be fewer shoe companies and jobs in New England.
But for now ''this is still a vital industry,'' states Bruce Goral at New Balance. ''The companies here in New England are competing smarter. We know we can't make cheap shoes. Just as GM and Chrysler can't make cheap cars and compete with the Japanese.''