DON'T THEY make you feel ashamed? You know, those little packs of joggers who commandeer the sidewalk at lunch time, huffing and puffing while you motor down the street in search of a chalupa with extra sour cream.

It's not just the shame of the fast food that gets to you. It's also the unused health club membership, the clothing-strewn rowing machine and the Tae Bo tape with the unbroken seal. Sure, that could be you out there prancing and laughing with your own co-workers. But wouldn't they think you were insane for floating the idea of a lunch-time running group?

First of all, the people you work with probably won't judge your sanity by that one suggestion. Secondly, they might think it's the first good idea you've had in a long time. Many people need and welcome the encouragement and companionship of others as they exercise, and the workplace running/walking group can be a great resource for that type of support. Of course, there are some secrets to managing and maintaining this type of group.

Jan Plewes and Dick Schneller, of Octagon Athlete Representation in McLean, have been taking lunch-hour runs together for the past nine years. They meet at noon on Mondays, Wednesdays and Fridays, come rain or shine. Most days, anywhere from three to five co-workers join them for a run that is just under four miles.

"The really important thing is to have a set time," says Plewes, who is the company's senior vice president for financial services. "You have to make it easy on people. You can't say you're running at 12 and then change it to 12:30 or 1. It's pretty well-known that we always run at noon, so anyone who wants to go can meet us at the elevators then."

Since the running ability of each group member is different, their overall attitude is decidedly noncompetitive. They typically maintain an 8 1/2- to 9-minute-per-mile pace as they follow a loop course around the streets near Tysons Galleria shopping mall.

"Probably the only reason we've been able to maintain the group for so long is that we've kept it relaxed," says Schneller, the company's client accounting manager. "We end up talking to each other a lot during the run, so that slows the pace a bit, as well."

Informality and a noncompetitive atmosphere are both important ingredients for a burgeoning workplace running group. No matter how interesting you might find the subject, talking incessantly about your split times will only make your fellow runners wish they had gone out to lunch for margaritas. You also want to be careful not to push new runners too hard. If someone is over the age of 45 or has never before run for extended periods of time, you should insist that they clear this type of exercise with their doctor beforehand.

"I would even suggest getting everybody in the group checked out before you start," says Dan Trone, a research physiologist who studies injuries within recruit populations for the Department of Defense. "The risk of injury is the big thing. In general, what I tell people is that it's better to be conservative. Take it easy and be sure to warm up and cool down properly."

If someone in your group would rather walk than run, try to find another company employee who might also be interested in walking. It's not important for group members to keep the same pace. The key is having more than one person at each pace. That way, everybody has a conversation partner. This is especially gratifying when you want to put the bad mouth on that hot shot up ahead who's running a 6-minute mile.

"Get some feedback on variety and what people would like to do," Trone says. "The return on time invested is very important, and you can get a lot of bang for your buck by just taking a brisk walk or jogging."

Plewes and her fellow runners even managed to keep things slow and steady when a speedy new Octagon employee, high-hurdling legend Renaldo Nehemiah, joined them for a recent midday run.

"He didn't seem to mind the pace," Plewes says. "And it was good, because we talked about business and updated each other on things we were doing."

Plewes says the runs are a good opportunity for people to bounce ideas off one another. She thinks people talk more freely outside the office. Both she and Schneller agree that the physical exertion can also relieve stress and salvage what might have begun as a really bad day.

Just because you run or walk during your lunch break, it doesn't mean you should skip your midday meal. Even if you're pressed for time after the workout, you should try to eat a light lunch or snack. Trone, who is also a triathlete, recommends eating fewer carbohydrates after a midday run. This can suppress a quick sugar swing that might leave you feeling drowsy later in the day.

"I think it's pretty artificial to eat three huge meals, anyway," Trone says. "Eat smaller portions throughout the day, and don't use caffeine to swing back when you get dozy."

The Octagon runners have access to two things that are necessary for maintaining a lunch-time running group: on-site showers and changing facilities.

Sadly, a splash of water and a swipe of Speed Stick won't do the job after a three-mile run. And that's why anyone who hopes to form a group in a showerless situation will probably have to pitch the idea of after-work runs. That could be a tough sell. But even if you're only able to recruit a handful of like-minded co-workers, the benefits can be rewarding.

"A group that plays together probably works well together, too," Trone says. "It can allow people to achieve their fitness goals, and there's a carry-over of that physical well-being to mental health. It can increase morale."