The other day I almost tore a partner’s ACL off the bone, which would have required him to have surgery and many months of rehabilitation. What happened exactly? I was more experienced and a bit bigger than my training partner that day and we were doing some no gi sparring. Because of the experience discrepancy I was hyper-focusing on a couple of very specific positions, namely Ashi Garami and the 411. (This is a form of Targeted Sparring which is a great tool to use when you're going against less experienced training partners - by limiting myself to only a couple positions and one submission it makes the match more even and better training for both of us.) So we’re rolling, carefully and respectfully... I’ve tapped my training partner out a few times with heel hooks, all applied in slow motion...  He’s beginning to defend the leglocks more intelligently and I'm having to work a little harder to get them...  Everything is going the way it’s supposed to. Then it almost ended very badly. I had the Ashi Garami firmly in place, and was just finishing the dig part of the heel hook (where you get your wrist under his heel in preparation for finishing the lock).  And 99% of the time when I’m sparring that’s as far as I’ll go - no need to actually apply the heel hook.  At that point my partner typically knows he’s caught and will tap out. But this new training partner didn’t know when to quit.  He tried to escape by spinning. And, to make matters MUCH worse, he spun the wrong way! Spinning or rotating can be part of an effective heel hook defense, BUT NOT WHEN YOU GO IN THE WRONG DIRECTION!! Instead of relieving the pressure, spinning into the dig amplifies the power of the submission exponentially! If I had remained still, not moving, his wrong-way-spin would have slammed his heel into my forearm.   He would have full power heel hooked himself, which can tear all sorts of ligaments in the knee, the foot and the ankle. Fortunately I saw what was about to happen and completely released my grips without a second to spare.   The submission evaporated, he spun safely and ‘escaped.’ Then I sat him down and we had a good little chat about the dangers of spinning out of leglock if you don’t know which way to spin. Now I'm not here to vilify leglocks, because I've managed to train them safely for years.   And I've seen lots disasters and near misses on the mats with many other techniques and submissions over the years. So let's universalise a few take-home lessons from this incident… LESSON #1 - IF YOU’RE CAUGHT AND DON’T KNOW WHAT TO DO, THEN DON’T DO SOMETHING DYNAMIC!! This is certainly true of the heel hook example above, but this applies to any submission. Imagine an absolute beginner caught in an armbar from guard with no idea how to defend or escape technically. But he still doesn't want to tap out, and lacking a good plan, decides to try something dynamic and unorthodox. He turns 90 degrees to the side then does a flying belly flop onto the mat.  Or maybe he launches himself into a full power backwards somersault.  Or maybe into a breakdancing head spin. Do you think something could go wrong in those situations? Yes!  Very seriously wrong.  Snap, crackle, pop wrong! Introducing that much additional and unexpected momentum into a situation where  you don’t know exactly what you’re doing is guaranteed to lead to disaster. At some point a limb will end up in a vulnerable position and the heavy body in motion will result in a sprain, tear, break or dislocation. Yes, there are times when momentum is your friend for escaping submissions, but it’s a tool that you use rarely, in specific situations and with specific techniques. Don't get injured because your ego makes you unwilling to tap out. If you’re caught in a position or submission and you don’t know which way to turn then don’t turn! Instead 1) accept that you're caught, 2) open your hand and 3) tap it on your opponent a few times. Your jiu-jitsu will improve SO much faster if you're o