Not long ago I ran into my old high school friend.

Literally.

We were among the 3,200 women at Hains Point, participating in the Bonne Belle 10k (6.2-mile) race. My friend looked great in her pink shorts and sleeveless top, sweatband around her head, nervously shifting her weight from one foot to the other. She was ready.

I was ready too--ready to turn around, jog back to my car and go home. I wore my old blue jogging suit, old sneaks and shades. I usually run a mile and a half, three times a week, but my co- worker, Sandy, reassured me that even though I had never run in a race before, I would not have any trouble finishing.

The first mile was easy. The adrenalin was flowing, and I was hanging in there with the best of them. As my pace slowed, I saw my friends ease past me and I gave a confident yell: "I'll catch up with you later."

At the one-mile mark, the timekeeper shouted "Thirteen minutes. You're doing good." (That was just about my average for the race.) Before I reached two miles, I broke into a sweat, my legs tired, and I slowed to a fast walk. As I looked around and tried to determine the direction of my car, I heard shouts from the sideline. Several men sitting in lawn chairs were cheering me on. "You can do it! Keep going! Hang in there!" Not wanting to be embarrassed, I quickened my pace and resumed a slow jog. Applause!

I crossed the bridge over the Tidal Basin and the cool air from the water relaxed me. A wave of women passed by; I was running alone. But then I looked behind me, and my confidence soared: there were at least a couple hundred women back there.

I got my "second wind" and my legs and feet were working in unison. I realized that if I just kept the same pace, I'd make it to the end. Someone yelled, "You're doing great!" I gave a short wave, and a big smile.

Near the three-mile mark, kids lined the street holding cups of water. I grabbed a cup and tried to drink while running but the water spilled down the front of my suit. I grabbed another cup, stopped and gulped it down. When I reached for the third cup, I splashed the water on my face--just like on "Wide World of Sports." By now I was really pumped up and knew I'd make to the end.

Then my balloon popped.

A group of runners had already gone around the loop and were on their way to the finish line, headed by a 12- year-old. I was 45 minutes behind her!

I started walking, holding my head down, ignoring the edging from the sideline. Then I realized my friends would also soon be circling back toward the finish line. I didn't want them to see me walking. I jogged slowly at first, then began to pick up speed when I spotted them. "Hey, you're looking great. You're halfway there!" I grinned and as soon as they were out of sight, I resumed walking.

Close to the five-mile mark a woman about 50 pounds heavier than I jogged by. That did it! I was determined to beat her to the finish line.

I wiped my face, put on my sweatband and was back in the race. I checked behind me --out of 3,200 women, I was in the last 30! I struggled passed my large competitor, and soon the six-mile mark and finish line were in sight.

Photographers knelt to snap my picture. The ribbon had long since been broken, but I raised my hands and flashed a big smile. I did it! It took 84 minutes, but I finished. I walked around, taking my victory lap, waving and smiling. I was on an emotional high with no time for cooling down to stretch muscles.

Later that evening, the pain in my thighs was unbearable. Trying to climb the stairs was an ordeal. I had no idea just how out of shape I was. Even after soaking in a hot bath and rubbing on medicated cream, the pain persisted for three days. But next time, I'll be ready. HOT TIPS

Races will held throughout the summer, despite the Washington heat. In order to avoid the troubles I had, take the advice of Bubba Tyer, trainer for the Washington Redskins. Tyer says you should warm up by slow jogging and stretching, and cool down the same way to help prevent soreness. "Use caution," Tyer says, "it's no good to run six miles and have sore ankles and try to run six miles the next day. Don't push yourself. Listen to your body." If you do sustain a minor injury, Tyer recom- mends using the RICE method (rest, ice, compression and elevation) as soon as possible. If swelling or pain persists, see a doctor.

Three stretching exercises to use for warming up and cooling down are:

Calf stretch: Stand flat- footed about three feet from a wall with your hands on the wall for support. Lean forward--keeping your knees locked, legs straight and your heels on the ground--for about 20 seconds.

Quadricep stretch: Lie flat on the floor with one leg extended and bend the other, grabbing the ankle. Try to touch the floor with the bended knee. Another stretch is to stand on one foot, grab the other leg by the ankle and pull it up behind you. Hold for about 20 seconds.

Hamstring stretch: Place your foot on a chair or low table, keeping your leg straight and your knee slightly flexed. Grab the ankle of the extended leg and bring your head toward your knee. Hold for about 20 seconds. Repeat on other leg.

More tips:

Don't ignore warning signs of heat injury: throbbing headache, nausea, shivering, unsteadiness.

Drink plenty of fluids.

Get plenty of rest.

Don't eat a big breakfast before running.

Pace yourself--gradually increasing speed.

Try to run on soft surfaces, such as grass or dirt.