The lumbar spine receives the nerves that lead to your upper legs and you gluteus maximius and the gluteus minimus (butt) muscles.
Here are some interesting facts about lumbar pressure in various positions:
1. Sitting hunched over a desk- 200 lbs.
2. Sitting leaning back on chair with low back rounded- 150 lbs.
3. Sitting upright with feet elevated- 100 lbs.
4. Standing with leaning forward posture- 200 lbs.
5. Standing in proper alignment:- 100 lbs.
6. Laying flat on back- 55 lbs.
7. Laying flat on back with knees elevated- 25lbs.
There are easy ways to take pressure off of the lumbar spine and with the differences in compression and pressure, you can see how modifications to standing, sitting and lying down can make a big difference.