I know it seems ridiculous to spend $50-100 on a piece of injection molded plastic, but this thing[0] has been the best I've found for getting deep enough into my abdomen to loosen my psoas.
I bought one of these and was never fully satisfied with it. Do you put the prongs directly in line with your belly button? Just above or below it?
I simulate that with a lacrosse ball and a kettle-bell. I lay on my back, and put the ball about 2 inches to the outside of my belly button and then place the kettle-bell atop the ball. From there, I move it slowly down passed my hip/groin. Don't go too heavy on the kettle-bell. I don't go over 35# usually.
Thanks for recommending this! Just ordered one to try it out. I've found that foam rollers, even the knurled ones, don't quite dig in deep enough.
That is really interesting. I know some people use a kettlebell (the handle) which resembles the tool you are sharing without the nice flared base.
Kettlebells help the back in other ways as well...