I've used three methods to do this:

1] Make morphs for maximum extent of movement (swing back, swing forward, swing left, swing right). you can either use a model to move the original OBJ's vertices, and import the modified meshes as morph targets, or use Poser's morph brush. Keyframe the movements in Poser's timeline (swing left in frame 10, swing right in frame 23, swing left in frame 36...)

2] Rig the hair model as a figure, and keyframe the "pose" changes in the timeline.

3] Clothify the hair model and run through the animation as a dynamic cloth simulation. This method works well for layered hair models, but is unsuitable for models with intersecting panels.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5