Side, back, or front: what actually changes when you sleep, and the one habit worth fixing first.
You spend about a third of your life in one position, so it's a fair question. The honest answer is that position matters less than people expect, and support matters more.
Side sleeping
The most common position and generally a comfortable one. A pillow between the knees keeps the top leg from dragging the pelvis into rotation, which is where a lot of morning hip and low-back stiffness comes from.
Back sleeping
Fine for most people, and a small pillow under the knees takes tension off the low back. If you snore or have been told you stop breathing at night, raise it with your doctor rather than adjusting your pillows.
Front sleeping
The hardest one on the neck, because your head has to stay turned for hours. If you can't fall asleep any other way, a very thin pillow, or none at all, reduces the twist.
The habit worth fixing first
An old mattress or a pillow that no longer supports your neck will undo any position change. If you wake stiff and loosen up within twenty minutes of getting going, that pattern usually points at your setup rather than your spine.
