AS MUCH AS IT pains me to admit it, I owe a lot to my older brother. Without him, I’d never have become the self-assured tomboy that I am. Three years my senior, Allie never missed an opportunity to pinch, flick, slug or otherwise harass me. My right hand still bears the scar from the time he accidentally bludgeoned my pointer finger with a shovel, which moments before he’d used to drop a payload of freshly scooped New England snow onto my 10-year-old head.

Rather than tattling about such indignities, however, I gave as good as I got, employing tactics favored by underdogs everywhere: clawing, kicking and biting. There’s something to be said for enduring such painful forms of sibling rivalry. It taught me to stand up for myself and gave me the sense that, if my life ever depended on it, I could handle myself in a physical confrontation.

For old time’s sake, Allie and I still engage in the occasional wrestling match, but the 3,000 miles separating Portland from New York City, where he now lives, ensure that any such goofing around occurs infrequently. It also means that my home-schooled techniques for warding off would-be attackers have become a bit rusty. This is part of the reason I decided to sign up for self-defense classes at Portland’s One With Heart Tulen Center, which focuses on poekoelan, a blend of Indonesian and Chinese kung fu combat styles. Of course, facing my lanky older brother wasn’t quite as intense as staring down my instructor, Joel Much. At 5 feet 10 inches tall, the husky fourth-degree black belt and 16-year veteran of poekoelan towers a full six inches over me. But, Much reassures me from across the mat, “When it comes to defending yourself, size doesn’t matter.”

To overcome such obstacles, poekoelan focuses on honing awareness of one’s own body—from the ball of one’s foot to the back of one’s head—and understanding that even an undersized frame like mine can be used as a weapon for real-life, practical self-defense. These skills aren’t just for scoring points in some sparring match. The kicks and strikes you learn are meant to break bones and disable attackers.

While poekoelan, officially known as poekoelan tjimindie tulen (pronounced poo-koo-lawn shi-min-dee too-len), has been taught in the United States for more than 50 years, its appeal has recently surged thanks in part to the deluge of martial arts-infused blockbusters like the Rush Hour and Kill Bill films. In fact, nearly 7 million Americans participate in some form of martial arts each year. Locally, there is such a demand for poekoelan that One With Heart has opened two additional training centers in the metro area since 2004. The three centers offer everything from heart-thumping, bootcamp-style cardio workouts to meditative yoga sessions—but the company’s bread and butter are the poekoelan classes, which may offer the best way to blow off steam after a long day spent sparring with busted Xerox machines and short-tempered clients at the office.

But before I break a sweat, I need to learn the lingo. Much explains that he will be referred to as “Pendekkar” (professional) and I will be “Mas Rachel.” (Mas is a general title of respect.) These formalities, he tells me, are meant to foster a mutual courtesy between teacher and student. Then we get down to business: Much dons a pair of padded hand targets and shows me how to perform the “flower parry,” an open-handed move meant to block and deflect my assailant’s blows away from my body, allowing me the opportunity to really wallop him.

In contrast to other forms of martial arts like tae kwon do, which only teach very precise movements, poekoelan can be more dynamic. “You don’t feel put in a box,” says Much. “It’s very free.”

Over the next hour, as I learn the basic hand-blocking techniques and counter-attacks, I quickly realize that it would take years for my parries and punches to achieve the level of grace and might that Much exhibits. By comparison, my flailing arms and legs feel awkward and clumsy as I struggle to land a single strike on my targets. Much leans in to encourage me