One should avoid movements (mostly rotations and twisting in spinal area) which could cause shift of spinal vertebrae.
The explanation applies not only to yoga postures but many kinds of sport as well.
One of the main principles of the classical yoga system is Ahimsa (“not doing harm”). This principle one should apply to nonviolence action regarding others and oneself (including own body).
Practice of different tricky postures could be really dangerous as it can cause shifts of spinal vertebrae.
|| Let’s look why one should avoid any kind of shift of vertebra.
Simply, as you may know, the central nervous system (the brain and the spinal marrow) controls and gives commands to all organs and systems of our organism. Nerve signals from the brain passing the spinal marrow go to organs and return back to the brain the same way.
| If any of vertebrae shifts it can press on or even block nerves connecting organs with the central nervous system. That results into different organs disorder and disease which are common. So any rotations and twisting in spinal area should be avoided.