Oxygen Uptake and Endurance Fitness in Children: A Developmental Perspective

TIn adults, maximum oxygen uptake (VO ₂ max) serves as a useful indicator of cardiopulmonary reserve as well as performance in endurance exercise events. Whether VO ₂ max can be interpreted in the same manner in children is less certain, since maximal oxygen uptake per kg body weight remains essentially stable during the growing years while endurance performance improves dramatically. Gains in ability in endurance events may be achieved through improved submaximal exercise economy, qualitative changes in oxygen delivery not indicated by VO ₂ max, or the development of nonaerobic factors (speed, strength). Maximal oxygen uptake in children may therefore be a less valid indicator of cardiopulmonary function, endurance capacity, and response to training than in adult subjects.