If you're experiencing chronic or intermittent low back and/or neck pain, a simple a quick breathing check could provide great relief. Poor breathing mechanics, or chest breathing usually signals an increase in respiratory rate, which is an indication of stress in the body. Stress can shut down stabilizing mechanisms of the spine, and cause muscular and neurological responses that can cause pain in the muscles as well as tightness and overall discomfort.
Here's a quick self assessment:
1) tie a small string around your belly button line, an elastic waist band will work fine as well.
2) Take a deep full breath, and feel for full expansion in the low belly, below the belly button, in the solar plexus just below the rib cage, in the rib cage, and the chest area. If you are experiencing an inability to full expand and fill any of these areas, you have some locked respiratory muscles.
3) Release your diaphragm and abdominals. Use your fingers to trace your rib cage, right at the point where the abdominals connect. Carefully apply ever increasing pressure to this area of the body. Dig under the rib cage and feel for hot spots in your musculature. As you massage gently, these hot spots will begin to release. Be careful with your organs in this area, never force a position or apply pressure to anything that isn't the muscles of abdominals.
4). Take 5 deep belly breaths and retest. Repeat as needed.
5). If you find that you are often locked up in this area, you have stumbled across a likely contribution to your low back and neck pain.
If that is the case, spend 5-10 minutes, 2-3 times a day to revisit this exercise until your default respiratory state is that of full breathing from the diaphragm.