Open wedges and closed wedges: Many of you will be aware that a big part of my teaching is bound up with the of using our body to create IMMOBILIZING WEDGES around important parts of our opponents body to hold them in place while we a given move. A BIG part of what we call Jiu Jitsu is the of setting these wedges around an opponent in a mechanically advantageous fashion – this one of the main basis of efficiency in our sport. The best wedges are generally CLOSED wedges, where our limbs lock into each other to securely hold the wedges in place. A triangle is a set of wedges around our opponents head and and it is CLOSED insofar as the locking of your legs mechanically locks the wedges in place. Closed wedges are not always possible however. More often we have to with OPEN WEDGES and now we need a substitute method of holding them in place. Sometimes its body weight, sometimes it is muscular exertion. Here I am working with the arm bar (juji gatame) – standard of this are examples of open wedges. You can see I have to make up for the open wedges through good body positioning and muscular tightness around the head and . Directionality of force becomes extremely important now if the lock is to be effective against stout resistance. If you are a shorter limbed athlete like me, learning to work effectively with open wedges is extremely important. Every time you practice your application of them, have your partner try to pull out – that will immediately tell you how effective your placement really is.