When Marines put together a sporting event involving nearly 17,000 people (three quarters of whom are civilians), they approach it tactically and strategically, as if establishing a beachhead. It's an operation, they say, like any other military operation.

The 15th Marine Corps Marathon Sunday is no less intricately planned or methodically detailed than in previous years because of another military operation going on half a world away.

Enough observers thought Operation Desert Shield would significantly hamstring race organizers in terms of manpower and supplies that Quantico took to the offensive in its media information packet: How can the Marine Corps justify a major sporting event in the shadow of recent events in Kuwait and the Middle East?

How can all these Marines be standing around handing out cups of water when men and women are sweating it out in the Saudi Arabian desert?

For the Marines, it's not that there exists no tangible difference between war and a road race; they see both as operations with goals worth pursuing.

"My expertise is in organizing operations and that's how we all approach" the race, said Capt. Marshal Fields, race director. "There's been no grousing among the Marines about wanting to be over there. Marines are trained in different areas; we're not all set up to respond in only one specific area. There are Marines responding all over the world right now. The entire Corps is not in Saudi Arabia. There will always be Marines back in the States.

"We're constantly rotating duties. It's possible we could rotate there and they could rotate here. Right now, there is no impact on the race."

Locally, Operation Desert Shield most affected Bethesda Naval Hospital, depleting doctors and nurses from the traditional source of the race's medical support.

"The only thing the operation in Saudia Arabia has affected is the medical support," said Lt. Col. Lorraine Goodrich, a public affairs officer. "We got a great deal from Bethesda and there was a massive exodus from there. We're backed up with reservists normally used on the race course. Any medical people still interested in volunteering are welcome."

The race has never been postponed or canceled because of a military operation. "Will that ever happen? You're asking me to speculate on something I can't speculate on," Fields said.

Most of the 2,000 Marines assisting along the 26.2-mile route are volunteers. "They could be helping out at the marathon or watching TV at home," said Fields. "They'll still be getting paid as Marines. We're Marines 24 hours a day."

About 60 percent of the runners in the race, the third-largest marathon in the country this year, are first-time marathoners. Most of them use this race as their first foray into long distance racing specifically because of the presence of so many Marines. There are always enough space blankets, water, triage units and guarded tents for personal belongings, not to mention Marines urging participants to take the next painful step. No prize money or appearance money is offered to attract top-flight competitors. The focus of the race, say the Marines, is the average marathoner.

Because the race attracts so many beginners, medical support is heavily stressed. "We probably get more first-timers in trouble than other races," said Cmdr. Robert Schultz, Quantico and marathon medical director. "Last year we had about 400 injuries and about half were musculoskeletal or other ones that just come with the territory of running long distance or exposure. And the other 50 percent were exacerbation of previous medical conditions."

Approximately 300 medical people and 20 ambulances are expected this year. There also are volunteer ham radio operators on the course to coordinate emergency response. There are eight aid stations, and Georgetown, George Washington, Capitol Hill, Arlington and Bethesda hospitals, as well as National Hospital for Orthopedics and Rehabilitation, are on alert on race day.

"We don't have the abundance of people we've had in the past but we have plenty to provide medical attention for a safe race," said Schultz. "There are so many people in Saudi Arabia, we've not gotten as much support from usual sources but we've gotten support from other sources," including neighboring military facilities not usually contacted.

"We're prepared to take care of anything that happens in the vicinity of Washington, D.C., on that day."