They especially need to engage the "rib anchor" muscles to prevent swaying / arching the low back. Then in case the rib anchor isn't quite up to the job (it has to work very hard in cobra), the inner corset is helpful for protection.
Some people are stiff enough in the low back, they are not able to sway at all - these people can do cobra with less caution. They'll be working on L5-S1 flexibility, which is a good thing.
33 min 19 sec ago
09/10/2008 - 8:36pm