Endurance, muscle tone and mental concentration are the attributes most commonly associated with the sport of racewalking.

But racewalkers are also helped by possessing a thick skin.

"I commute to work (on foot) and when I'm walking through McLean, I get four or five catcalls per commute," said Tom Hamilton of Arlington, the coordinator of the area group.

"You usually get kidded about how many propositions you get. We were originally going to call ourselves the Capital Streetwalkers rather than Racewalkers, but we figured the women wouldn't lide it."

Most washingtonians'only opportunity to witness racewalking comes every four years during Olympic broadcasts when the television cameras feature the would class walkers, strutting into the stadium, hips weiveling and arms flailing, entering the final 100 yards of a 20 or 50-kilometer (124 or 31-mile)race.

But for area residents who visit East Potomac Park on weekends, racewalking is not an unusual event.

The Potomac Valley Racewalkers, who have been adopted by the Potomac Valley Seniors Track Club after an infancy as the Capital Walkers, made its own play for international notice last August.

During a 24-hour urnning marathon at Ft. Meade. Md, which started Aug. 6 at 1212 p.m. an eight-man team walked 168 miles,1700 yards by the same time the next day. The walkers eclipsed the old mark of 162 miles, 275 yards, set by the Colorado Track Club in 1973, with nearly an hour to spare.

The feat does not become a sanctioned would record, however, unless three attempts have been recorded. The group has not been able to locate a third try, Hamilton said.

Racewalkers abide by only two simple rules. One foot must be in contact with the ground at all times and the nack leg must be completely straight momentarily on each step. If one foot is not in contact, the foul is called lifting or floating. Not straightening the back leg is called creeping.

The Capital Walkers were formed 21/2 years ago by Sal Corrallo, who presently serves as the Potomac Valley Amateur Athletic Association racewalking chairman.

Club members say Corrallo has spent most of his spare time during the past two years developing the sport in the area. There are now about 10 regularly active walkers in the group and the total membership fluctuates around 25, including four or five women.

Racewalking particularly appeals to runners who would like to improve themselves competitively. Many of the Potomac Valley seniors runners have added walking to their repertoire and compete in both.

"In nationals running, it's almost impossible to break in," said Hamilton, who was not eligible to join the seniors until he turned 30 in April."In walking, it's such a small guoup, you're at least not outclassed. It'ssort of a nice element. You go to nationals in racewalking, you know everybody in the country."

Racewalkers insist their sport is actually suited to more people than running.

"I think one thing I would stress to most people is that the sport itself is open to a wider variety of people," said Paul Robertson,38, an Oxon Hill resident, who after years of running now splits his time with walking. "It's open to a wider variety of physiques. Running races are heavily favored to strong muscle on a light frame. Anyone can racewalk.

The racewalkers also have younger converts, such as 17-year-old Paul Levandoski, a senior at Woodward High School in Bethesda, who simply finds he's better at racewalking than the cross country and track his school offers.

The racewalkers are always looking for a place to stage a race. They try to hook on with already established running competition whenever possible.

They also don't pass up an opportunity to advertise for new members. Corrallo, taking advantage of the inevitanle gawkers, often writes his name and phone number on the back of his shirt inviting spectators to "try walking" or advising them that "walkining is better."