The knee is a hinge joint. It’s designed to flex and extend with the thigh bone (femor) and the shin bone (tibia) in the same plane. A healthy joint can tolerate a certain amount of torquing or poor distribution of the body’s weight on occasion, but repetitive movements of that nature and /or severe uncontrolled movements can lead to permanent damage. Healthy knees are stable when straight (extended), but become slack when bent (flexed.)
Knee damage among martial artists is all too common, and the causes may or may not be self-evident. Martial artists whose practice includes kicks that require pivoting on a support leg or which involve landing leaping maneuvers may be intimately aware of the risks. However, the first martial art that I ever trained in had no twisting / pivoting kicks and few leaps (that were rarely practiced), but knee injuries were epidemic. The culprit in this case was low postures which required the thigh to be turned out (externally rotated and abducted) with the knee deeply flexed.
Well, I should say those postures were the culprit in conjunction with lack of flexibility and/or strength in all the right places. This isn’t to say that the individuals who developed knee problems weren’t strong or flexible, but the areas that needed work weren’t necessarily the big muscle groups that leap to mind when workout time comes around. Emphasis on the big muscle groups (quadriceps and hamstrings) with neglect of the muscles involved with adduction, abduction, external rotation, internal rotation and stabilization can create some problems. If you’re a runner or a weightlifter (with good form) you may be able to get away with such a stretching and strengthening emphasis. [Note: I’m not advocating such an approach for anyone. What I’m saying is that if your knee is only worked with the knee straight below the hip and pointed forward in a hinge fashion, your risks are not the same as someone who works with a flexed knee with the thigh turned out. The likely injuries are different.]
To do a posture like the one above, one needs the flexibility to keep the knee wide enough so that it points the same direction as the toes. The joint shouldn’t be wrenched or torqued with load on it. The four ligaments (Anterior Cruciate Ligament [ACL], Posterior Cruciate Ligament [PCL], Medial Collateral Ligament [MCL], and the Lateral Collateral Ligament [LCL]) and the surrounding musculature keep the joint snug during movements. And, as mentioned earlier, when the knee is deeply flexed it’s more sloppy than when extended.
-Increase flexibility in the muscles that internally rotate and adduct the thigh: When one goes into a wide-legged stance, one’s thigh is pulled away from the body’s center-line (abducted) and the thigh externally rotates. If the muscles that act in the opposite direction (pulling the thigh back on center and rolling the thigh inward) are too tight to allow the knee to move into proper position, then the load of the body weight will be going into the ground through a kinked joint. Furthermore, one will end up torquing through the joint as one moves. Below are a few hip openers that will help one achieve the requisite range of motion.
-Strengthen the muscles that stabilize the knee-joint. One begins this process with the usual suspects of leg exercise. One just needs to focus intently upon alignment. Here are a few of the exercises you may already be doing.
As one needs more challenge, one can achieve it in the usual ways (single-legged, unstable surface, add weight, or combinations thereof.) Below are a couple of variations that combine single-limbed work with an unstable surface.
-Save static stretching for after the joint has warmed up. It used to be common to begin a workout with static stretching. While few do this anymore, it’s a practice that needs to be replaced. Stretch warm.
-Don’t neglect the opposing muscle groups: When I said that one needs to increase flexibility in adductors and internal rotators, that doesn’t mean to ignore the opposing muscles. Nothing good comes of stretching or strengthening in an unbalanced fashion. Your musculature works as a team with agonists, antagonists, and stabilizers all working in conjunction to produce effective movement.
-Don’t go overboard with stretching: If your aim is to be a contortionist, then by all means go ahead. However, highly flexible martial artists need to be concerned about joint laxity. Laxity is when the joint gets so loose that it’s vulnerable to popping out-of-place. A martial artist needs a balanced style of fitness. Extreme flexibility results in weakness and lack of joint robustness, just like extreme strength training produces a body that lacks range of motion and stamina.
Most importantly, don’t ignore pain when it’s still at the minor twinge point. If you have knee pain you’re doing something that joint doesn’t like. One should reevaluate your movement and, if necessary, considering stepping back from your current practice to work on capacity building exercises.
Leaping maneuvers are ever-present in martial arts movies and in some martial arts (e.g. Indian Kalaripayattu and some forms of Kung fu). However, these acrobatic techniques are rarely seen–and are even less often successful–in combative encounters (neither in sport nor in the real world–excepting those sports that highly reward such maneuvers and create rules that make them feasible for entertainment value.)
Why leaping, spinning wildness is popular in movies is easy. We thrill to see extremely demanding action that draws ooohs and ahhhhs. It’s the same reason one wants to watch a parkour runner vault over a car (presuming it’s not one’s car), even when it would be infinitely more practical to walk around it. It’s why we want to see gymnasts tumbling and flipping through the air even though walking across the floor is both easier on the joints and less hazardous.
However, the question of why martial arts that aren’t purely for entertainment practice leaping maneuvers. Even a few of the quintessentially pragmatic Japanese martial arts, which follow the motto “eliminate the extraneous” have some leaping techniques. One of the schools I’ve studied, Kotō-ryū Koppōjutsu has a scroll devoted to leaping techniques, despite the fact that it’s otherwise a grounded system–both literally and figuratively. Muay Thai, which also values tried and true winning basics over snazziness, also has leaping knee strikes in its repertoire, though one doesn’t see them a lot in fights. It’s true that the arts that emphasize practicality but have leaping and spinning techniques tend to have a different approach to them. The Kotō-ryū Hichōjutsu (that school’s leaping techniques) emphasize eliminating big wind-ups, and going straight into the leap from a natural posture. This gives one less air, but is much less obvious. It’s particularly useful if you don’t really want air, but you just want to leap as much as you must. But why leap at all?
There are a number answers to this question. First, while it’s hard to make aerial techniques work, when they work, they can be devastatingly effective. There are few ways to put more power into a strike than to literally put all of one’s body-weight in motion under the force of gravity. There’s understandably something unsatisfying about this explanation. I think it mostly has to do with the dearth of second chances in combative encounters. Few second chances make one want to have the highest likelihood of success on the first go.
Second, while tried-and-true, go-to techniques work because they are hard to defeat and /or they minimize one’s risk of a fight-ending counter, some techniques work because they catch the opponent off-guard. Such techniques work because the opponent can’t believe one is actually trying something so wild on them. However, failing to anticipate the unusual, the opponent hasn’t trained a response into themselves. This answer gets us somewhere in cases where either the situation is dire or one knows something about the opponent.
Third–and I would argue most importantly–these techniques produce explosively powerful legs that are beneficial to a martial artist even when he stays on the ground. In other words, maybe they are more important in the role of capacity building than they are as actual techniques to be emulated.
Finally, there’s one more reason that is important but was last because I didn’t even learn this lesson until I was reviewing the photos for this post, and that’s that these techniques require a whole new level of bodily awareness and control. I would generally be considered to have pretty good bodily awareness. I’ve been doing martial arts a long time, have practiced various kinds of yoga and chi gong, and have done my share of other physical training. Still, when I looked at my photos I found that I often had body parts jutting every which way. While one may argue that one doesn’t need that brand of bodily awareness if one is not using that kind of motion, I think that it probably helps with one’s awareness at high-speed in general and that many arts don’t adequately prepare one for keeping one’s body under control when there are those extra forces (e.g. centripetal & centrifugal, and gravity) acting upon it.
One aspect of bodily awareness that is particularly important for these maneuvers is control of the eyes. In the arts I’ve studied, there has always been emphasis on the placement of the eyes. However, given all the little details one had to keep in mind, it was a reality easy aspect to half-ass. However, when one is leaping, and particularly if there is a spinning component, wandering eyes translates to crash and burn.
I’m not built for leaping. It’s not so much the leaping, but–in the immortal words of Tom Petty–“Coming down is the hardest thing.” I figured that getting to the level of Kalaripayattu training that involves a lot of leaping would be the end of that art for me. As I mentioned, there are some leaping techniques in the martial art I studied, but I was never particularly good at them. When I was young and had the proper body for it, I didn’t have the right mindset, and when I got older I was lacking the physical capacity for them. However, I’ve learned quite a bit about my body through the practice of these techniques, and I’m interested to see what level I can take it to.