Department of Mathematical and Technological Sciences, Norwegian University of Life Sciences, Ås, Norway.|Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America.|Department of Circulation and Medical Imaging, Cardiac Exercise Research Group, NTNU Norwegian University of Science and Technology, Trondheim, Norway.|Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America.|Department of Circulation and Medical Imaging, Cardiac Exercise Research Group, NTNU Norwegian University of Science and Technology, Trondheim, Norway.