title: New ideas on limitations to VO2max.
abstract: VO2max indicates maximal oxidative metabolic capacity (unfit subjects) or maximal O2 supply (athletes). The latter reflects integration of all transport steps from air to cytochromes. Every step contributes something; the importance of each contribution varies with conditions. Cardiac output seems most important at sea level; at higher altitudes, lung/muscle diffusion are more critical.
authors.affiliation: Division of Physiology, Department of Medicine, University of California, San Diego, 9500 Gilman Drive, MC 0623A, La Jolla, CA 92093-0623, USA. pdwagner@ucsd.edu
authors.forename: P D
authors.initials: PD
authors.lastname: Wagner
mesh_terms: D000531:Altitude; D002302:Cardiac Output; D015444:Exercise / Q000502:physiology*; D006801:Humans; D018482:Muscle, Skeletal / Q000502:physiology*; D010101:Oxygen Consumption; D010807:Physical Endurance / Q000502:physiology; D011653:Pulmonary Diffusing Capacity