It's another painful lesson learned at the American Martial Arts Studio in Alexandria, where business has been brisk since the Sept. 11 terrorist attacks. The 42-year-old Kim, who teaches anti-terrorism martial arts techniques, said his studio has been flooded with calls from people suddenly more interested in taking a box cutter from a terrorist than in buffing up their bodies with heart-pumping workouts.

Instructors at several martial arts studios in the Washington area confirmed the trend. They noted an enrollment spike that includes police officers and military personnel, as well as federal marshals newly assigned to keep the skies free of acts of violence. "It's been a strange twist in the industry," said Michael Wolfe, head instructor at C.S. Kim Karate in Germantown.

Wolfe said an increasing number of people who had participated in fitness programs such as Tae Bo and cardio-kickboxing are coming to his classes to learn self-defense. "The attitude of the students has changed. They are a lot more serious now," he said. Fred Bieber, 57, a pilot for American Airlines, signed up for hapkido classes at the Oriental Sports Academy in Falls Church after he heard that the Sept. 11 hijackers apparently seized control of the jetliners while armed with only box cutters and knives. Bieber wanted to learn how to subdue an assailant in the tightly confined space of an aircraft. He said he hopes other pilots and flight attendants will do the same.

"I simply want to be able to defend myself, my flight attendants and my passengers," Bieber said. "What if someone burst through the cockpit door with a gun or knife and I can only grab him with my hand? I want to know what to do."

Kim teaches an aggressive form of martial arts called Tukong, developed for South Korean special forces in the 1970s and '80s. Tukong includes chokeholds and other applications of deadly force, but Kim reserves those for expert students. Classes at his studio start at about $80 a month.

Although he knows how to dazzle visitors -- he can snatch an arrow in midair, for example -- Kim focuses his teaching on scrappy-yet-practical techniques. Before showing his students how to pin a knife-wielding terrorist on an airplane, he advises them to grab a seat cushion as a shield. One recent evening, he had his students practice in an old school bus to simulate conditions, including the space limitations, of an airplane cabin.

"It has to be realistic. Otherwise what's the point," he said. "We are not interested in teaching them a sport or entertainment. They are going to have to fight in the real world."

Instructors acknowledged that they do not know how their students would react in a crisis. But at a minimum, they said, martial arts teaches them not to be intimidated, a small victory over terrorism in itself.

"Terrorism is about causing fear," said Jeff Smith, who operates three karate studios in Fairfax County. "It's more about what could still happen to you than what has happened in the past. And that's where martial arts comes in. It gives people a certain peace of mind and self-confidence."

Rod Davis, a criminal investigations commander with the Stafford County Sheriff's Department, said his officers have been receiving training from Kim for two years. Davis said martial arts training is especially important now because many people are grappling with fear of another terrorist attack.

"People feel more vulnerable than ever before, and I think rightfully so," he said. "And if September 11th prompted people to take another look at their safety and join these classes, then that's the right thing to do." Jeanette Eash, 36, said that a year of training at Kim's studio has boosted her confidence but that she isn't sure what she would have done had she been on one of those ill-fated passenger jets in September.

"I've thought quite a lot about what I would have done," said Eash, a federal worker who lives in Alexandria. "I hope I would have been aggressive enough to put the situation under control, but it's very hard to imagine."

Still, she said, "I don't think I would have been as scared as I would have been a year ago."

© 2001 The Washington Post Company