Recreational:

Weiss, P.L., Bialik, P. and Kizony, K. Virtual reality provides leisure time opportunities for young adults with physical and intellectual disabilities. CyberPsychology & Behavior, 6:335-342, 2003. 

Yalon-Chamovitz, S. and Weiss, P.L. Virtual Reality as a leisure activity for young adults with physical and intellectual disabilities. Research in Developmental Disabilities, 29: 273–287, 2008.

Physical fitness:

Lotan, M., Yalon-Chamovitz, S. and Weiss, P.L. Improving physical fitness of individuals with intellectual and developmental disability through a virtual reality intervention program. Research in Developmental Disabilities, 30: 229–239, 2009.

Lotan, M., Yalon-Chamovitz, S. and Weiss, P.L. Virtual Reality as means to improve physical fitness of individuals at a severe level of intellectual and developmental disability, Research in Developmental Disabilities, 31: 869-874, 2010.