AS I PUSHED off for the first time, I was immediately reminded of ice skating, even if I was clad in shorts and a T-shirt to beat the summer heat. And though it wasn't ice that stretched out in front of me but asphalt, I was soon blasting down the street like a speed skater, my legs propelling me along with a sideways glide, my arms swinging rhythmically. Only in-line skating could provide such a rush.

In-line skating, or "blading" as it's nicknamed, is fast becoming the latest in trendy sports. The skates are more maneuverable than traditional roller, or tandem, skates. Instead of two wheels at the front and two at the back, in-line skates have four polyurethane wheels bolted in a row to a rigid frame. They look like brightly colored ice skates with rolling wheels rather than cutting blades, but there's more ankle support with these boots.

"It's a great time, a great way to exercise," says Bruce Witucki, a bartender in Old Town Alexandria who skates with friends at night after work.

"It's addictive," says avid skater and attorney Kelly Wrenn of Alexandria.

From a health standpoint, the beauty of in-line skating is its sideways motion -- there's no pounding as in running -- and the exercise it gives practically all your muscles, especially the heart, quadriceps, buttocks, back, even the abdominals.

Kathy Alexander, an exercise physiologist in Nashville, recommends in-line skating for her patients.

"It has a health benefit from the preventive side as well as the therapeutic side," she says. "It really strengthens your back extensor muscles. It's going to reduce your risk for back problems."

In-line skating is far from new. The concept of wheels set in one line was actually developed in the early 1700s by a Dutchman. In 1980, Scott Olson revived and refined the in-line design and founded Rollerblade Inc., before leaving to found rival firm SwitchIt. Olson believed the skates would provide ideal off-season training for National Hockey League players.

Today Olympic skiers, speed skaters, runners and rowers also cross-train in blades. Enthusiasm for in-line skating is rolling across the country to include kids who play street hockey, cyclists who skate when it's too cold to bike -- even football players.

Joe Patten, assistant athletic trainer for the New York Jets, puts players with knee injuries in the skates about 12 weeks after surgery to retrain and strengthen leg muscles.

"You want to cut down on the rotation of the knee joint," he says. "But the bottom line is, it's fun."

Greg Keim, a paralegal from Alexandria -- and probably one of the fastest bladers in the D.C. area -- spends much of his free time skating around Washington.

"Sometimes I go straight from work to the paths," he says, "and eat on the run."

It was Keim who inspired Wrenn to take up blading. Six months ago Wrenn was running on the George Washington Parkway path when Keim flew by on his blades. Wrenn managed to flag him down to ask where he had gotten his skates.

"It's a very user-friendly type of sport," says Wrenn. "The street is the limit."

I pondered these comments as I spun down a straightaway, body swaying to Basia on the Walkman. A cyclist approached, sweat running rivers down his face, pain knotted in the muscles of his calves. I know it was cruel, but I couldn't help chuckling as I rolled right past him.

IN-LINE SKATES

are available at most sports and skate shops in the area with prices usually ranging from $115 to $250. Skater's Paradise, 1508-A Belleview Blvd., Alexandria, rents in-line skates and protective gear for $15 a day; call 660-6526.

THE ROLLERBLADE RUN OR ROLL

will be held Aug. 11 at 8 a.m. outside Capital Centre in Landover. Participants may compete in one of three races: 5K run, 2K fun roll or 10K in-line skate race. Register at area Rollerblade retail outlets, or by calling 800/255-RISA. Advanced registration (postmarked by Aug. 3) is $5 for the 2K, $10 for the 5K and 10K. Fee after Aug. 3 is $8 for the 2K, $13 for the 5K and 10K.

WASHINGTON AREA ROLLERSKATERS

is a free club for both in-line and tandem roller-skaters. Members meet at noon the first and third Sunday of every month at Freedom Plaza, 14th and Pennsylvania NW; call 387-3389 or 301/799-8473.

Angela Soper last wrote for Weekend about teaching children to track animals.