Quadratus Lumborum, Back Hyperextension

[Aris Tsangarides]

I posted this in another thread but the issues on that thread were already resolved and it seemed like I was starting a new thread within a thread, so I just decided to post it as a new topic again instead.

Whenever I used to do exercises that involved hyperextension of the back, my "Lower/side" back would cramp up. The thing is though,  my erector spinae wasn't what was cramping. The way I figured it out was doing Iliopsoas stretches directly after, which soothed the low back pain but not the deep dull side pain, which remained for days on end.  Did a bit of research and figured that it had to be my Quadratus Lumborum, a muscle for which I haven't yet found a stretch that could be performed without a partner and that actually targets this muscle. Even foam rolling or using a tennis ball fails at successfully reaching this region.

 

As a way to deal with this issue, I try to always perform exercises with a "stacked" spine or at the bare minimum to be mindful of my coccyx being "tucked", which reduces pulling tension on my Iliopsoas and to some degree on my QL.

1)Are there holds/exercises where the back shouldn't be tucked? 
(in martial arts, tennis, swimming, and many other sports they teach you that being stacked is how you control your body as one single unit)

2)Is the QL involved in hyperextending the back? or in anterior pelvic tilt?

3)Are there any good solo QL stretching exercises out there?

4) Say you have tight hip flexors, hamstrings or any muscle you want. It's tight and you can also feel a pain that resulted from this tightness. Do you recommend stretching?(I assume yes) 
BUT do you recommend strengthening:
-after the pain has gone away?
-while there's pain, but to train the muscle within the confines of what one would consider tolerable pain/not debilitating pain?
-what if you haven't been strengthening the muscle, but kept stretching it correctly for a number of months and there is an increased range of motion and flexibility but still some residual pain. Could this be because of a lack of training this muscle? 
Should you start strengthening it? 

I would really appreciate Kitlaughlin's input on this(as well as anyone else that wants to shed some light on this issue)

[Biren Patel]

 

3)Are there any good solo QL stretching exercises out there?

 

 

I can't really answer much here. But, speaking of Kit Laughlin, exercise 29 in Stretching & Flexibility presents a nice QL stretch.

[Jason Dupree]

QL is involved in lifting the pelvis, ie making the leg shorter. Hip circles will stretch it, I don't know of any others though.

Edit: more thorough answer

We call this tucked position a hollow, where the pelvis is tilted posteriorly and the spine is straightened. It is very important for stability and safety. However, when doing back extensions, you want to arch your back. In either case, lower back pain will be caused by hip flexor tightness. QL is more of a stabilizer and lateral hip rotator (it is usually why someone has uneven legs).

As for stretching, stretch hip flexors and QL and hip extensors. As far as I know, strengthen if you are uncomfortable, but not through pain. Hopefully Kit or someone better at stretching will answer