1. Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong, China
2. Gait and Motion Analysis Laboratory, Department of Rehabilitation Sciences, Faculty of Health and Social Sciences, Hong Kong Polytechnic University, Hung Hom, Hong Kong, China
3. Department of Biomedical Engineering, Boston University, Boston, MA, USA
4. Department of Exercise Sciences, Brigham Young University, Provo, Utah, USA