Thor is a Professor at the Auckland Bioengineering Institute (ABI) and has a joint appointment with the Department of Engineering Science & Biomedical Engineering at the University of Auckland. He completed his Ph.D. in musculoskeletal biomechanics at The University of Western Australia in 2000 and was a postdoctoral fellow in the Bioengineering Department at Stanford University from 2003 to 2006. Thor established Stanford's Human Performance Laboratory as the Director of Research and was a faculty member in the Department of Orthopaedics at Stanford from 2006 to 2010, before returning home to New Zealand in 2011. He leads the musculoskeletal modelling group at the ABI.