One common problem I see in posing is the stiffness in the hip, torso and shoulders.  This one of the big hallmarks of the bad "Poser Look".

When using many of the stock figures such as victoria or michael, people assume that the ZERO position is the "normal" standing pose.  This is not at all true.  The shoulders are set too high, the spine is not curved correctly and the hip is rotated wrong for a person standing at rest.

When I start a new pose, I always start by dropping the shoulders to -10, rotating the hip back and bending the chest and neck forward.

Gabriel Sabloff
TIRADE STUDIOS