In this video I show the Straight Arm Lock off of the Americana setup. This is a fairly common defense for when you start to dominate the arm.
I focus mainly on the defense for when people straighten the arm and then turn the thumb down towards the floor. I do this, as opposed to the traditional thumb towards the ceiling option because if they are advanced enough to straighten the arm then they are probably also smart enough to turn their thumb towards the floor. If you watch the whole video I do briefly address what to do if your opponent does not turn their thumb down, it should be fairly easy.
The main focus of this video is going to be dominating the position. I have seen this many times when your the person being submitted straightens out their arm and the person on top keeps their base back to maintain mount. This results in not being able to build enough pressure to actually break the arm.
When someone straightens their arm it is important to move your head forward and base it on the floor. This move does require a certain amount of commitment as it will alter your base when you put your head on the floor by taking weight off of your hips. If you leave your hips in that mounted position and just try to submit them with your head on the floor more than likely you will either end up in Half Guard (and then ultimately give up your back) or they will put their thumb in your armpit, shrimp and come out the back door.
I deal with this problem by brining my far side knee up and dominating beside the head. I quickly go over the placement of the leg based on the size of the person that is doing the submission but the truth is where you put the leg also dictates how much of a commitment you are making to the arm. If you go on the far side of the head (where I typically go because my legs are long) you can squeeze your knees togather and add a good bit of domination to this position. If you go over to the far side of the head the domination of the arm is very good but in the event that they do come out it’s going to be a tough scramble. I recommend using the three variations and seeing which one works best for you.
Also take note of the way that I rotate the arm to submit my opponent. This is a good bit different than I was originally taught. As you advance through the ranks you will find that armbaring someone is more about going against the joint than going in any real direction. I use the thumb as a good gauge here and rotate the arm horizontally instead of vertically.
Thanks for watching!