Am I allowed to move?
If you need to occasionally stretch a muscle during a pose that is fine as the group doesn't want you to be suffering too much discomfort. Any other movement should be avoided where possible. If you are in pain and feel you will need to end the pose ahead of the agreed time it is appreciated that you give as much notice as you can to the artists so they can begin to bring finishing touches to their work early.
Copyright LifeART 2008