Hi, I no longer run, but I figured this board is full of knowledge.
When I lay down on my back and try to press my lower back into the ground, my left side presses in a lot more. When I sit on the floor with my back against something, my left glute/butt cheek is more on the ground than my right side. When I lay on my stomach, my left side is pressed more into the ground. I tend to sleep leaning towards the left.
What could this be?