Hello, I would start reading ESURF (extension of SURF), 3DSIFT, HOG3D. Also I'd check HOGHOF and MBH features as well. Hope this helps :]

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Action recognition with improved trajectories

H Wang, C Schmid

Computer Vision (ICCV), 2013 IEEE International Conference on, 3551-3558

Action recognition by dense trajectories

H Wang, A Klaser, C Schmid, CL Liu

Computer Vision and Pattern Recognition (CVPR), 2011 IEEE Conference on

Have you looked into Body Surface Context (link 1) or Trace Transform (link 2) ?

http://ieeexplore.ieee.org/xpl/articleDetails.jsp?reload=true&arnumber=6722961

http://www.image.ece.ntua.gr/papers/792.pdf