1. Cardiovascular Physiology and Rehabilitation Laboratory, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
2. Experimental Medicine Program, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
3. Physical Activity and Chronic Disease Prevention Unit, Cognitive and Functional Learning Laboratory, University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
4. School of Kinesiology and Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
5. Professor Emeritus, University of Toronto, 55 Harbord St, Toronto, ON, M5S 2W6, Canada.