In our school, students learn a technique called Ridge Hand Strike at the Fourth Geup level.1 This technique uses an unusual striking surface—the muscle and bone on the inside edge of the hand, revealed by folding the thumb underneath the palm—which gives the technique its name. Like all strikes, it follows a curving path to accelerate into the target from an oblique angle. The arm is fully extended (elbow slightly bent so it’s not locked) so the technique has great speed and power and a long reach, three obviously desirable characteristics.
The very arm extension that gives this technique its speed and reach creates the risk of a biomechanical liability: if in striking a heavy target that resists the impact (such as a heavy bag) a practitioner’s arm is too relaxed, the sideways force may hyperextend the elbow.2 That is, the momentum of the arm and the snap of the hips that makes the technique so strong can bend the elbow backward in a way the joint doesn’t allow. This will cause pain at the very least, and possibly damage to the bones of the joint or the ligaments that hold the elbow together. It’s obviously smart to avoid this, but it only takes a small lapse in attention to make it happen, and if you’re training intensively in this technique, it only takes one out of many repetitions to cause this kind of damage.
Adding one motion at the moment of impact can help safeguard the practitioner’s elbow: at the instant the technique “snaps” into full extension, make a conscious effort to contract the biceps of that arm. This is the same tightening that snaps the end of many hand techniques, from a front punch to a downblock—just more so. The amount of strength is proportional to the weight of the object striking: less for a focus mitt, more for a heavy bag. This relocates the stress of impact to the springy muscle tissue instead of the much less flexible bone or connective tissues. It’s highly unlikely that this technique will create enough force to damage the muscle, but even if it does, remember that muscular strains almost always heal much faster than tendinitis, ligament damage, bone bruises, and so forth.
Protecting the body is its own reward, but flexing the biceps at the moment of impact has another benefit: more power and displacement of the target. If you try this motion on a heavy bag, you’ll see it right away. Instead of penetrating the bag a certain distance and stopping, the arm continues to pull the bag in that direction. This may give you ideas about new combinations. Try performing a reverse ridge hand strike in front stance; immediately after impact, as your contracting biceps pulls the bag deeper, open your hand and slip it around the bag; then pivot your feet and hips into the opposite front stance and perform a reverse elbow strike with the opposite hand. Use your imagination and practice to identify similar combinations that flow efficiently and logically together.
When drilling the Ridge Hand Strike with this refinement, there usually won’t be a heavy target to provide resistance. The practitioner should take care to flex their biceps without letting their arm bend beyond the usual angle of extension, i.e. just slightly bend to avoid elbow locking. This is similar to the way we practice snapping a roundhouse kick crisply into place in the air, rather than burying it deeply into a heavy bag or body shield. Context tells us whether we should use this controlled snap or follow through to deepen the penetration into an actual target.
Martial arts techniques have evolved over a long time into the forms we know today, and that evolution includes refinements to both ensure the safety of the practitioner wielding the techniques and increase the effect on the object of the technique. This nuanced finish to the classic technique may provide insight into how that evolutionary process works.
1 I was talking to the head instructor of another traditional Tae Kwon Do school (Master Doug Cook, Chosun Taekwondo Academy, Moo Duk Kwan) who said, to my surprise, that many modern schools don’t teach the Ridge Hand Strike. “The fact that you know this technique at all says a lot about where you come from and what your school values.”
2 In contrast with a light target that yields—a focus pad, say, or the head.