The cue I like to use to get people recruiting their transversus abdomenus correctly is to pretend you're putting on a really tight pair of jeans and you don't want to get anything caught in the zipper.
OK, now hold that for 10 sec, rest 1 second or 2 then repeat. Do this for at least 1 min, at least 2 times per day. More often if you can.
I also like to get people doing psoas recruitment exercises. There's some good research out there to support the idea of the psoas acting as a stabilizer for the pelvis and low back. It works really well for some people with chronic SIJ issues. This muscle is a little harder to get to work. The easiest way is to lie on your back, have DH gently pull on your leg, by the ankle and then you try to suck your thigh bone back up into your pelvis. The first time you try, do it as hard as you can and have DH rotate your leg, there will be a lot of resistance. Then do it again but at 25% effort, this should stop you using your quads and hams too much. At that effort level DH should be able to rotate the leg with minimal resistance from you. If there's resistance, you're using the wrong muscles to perform the action. It's hard to explain. It's more of a demonstration type of exercise and even with demonstration a lot of patients struggle with this. So if you don't get it, don't get hung up on it. If you do get it do the exercise on both sides, use the same 10 sec hold, 1 min, twice per day. I might try to post something on yuotube about this. After Christmas, maybe.
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