1. Department of Mechanical Engineering, The University of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand e-mail:
2. Department of Exercise Sciences, Faculty of Science, The University of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand e-mail:
3. Mem. ASME Department of Mechanical Engineering, The University of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand e-mail: