ABSTRACT
This chapter provides a synthesis of knowledge regarding changes in aerobic and anaerobic metabolism during growth and maturation and the effect of exercise training. The process of growth and maturation is associated with profound changes in markers of aerobic and anaerobic muscle metabolism, which essentially mirrors documented improvements in athletic performance for events requiring predominantly anaerobic and aerobic metabolism. Four key parameters have been identified for the assessment of an individual's aerobic fitness: maximal oxygen uptake, the lactate or gas exchange threshold, exercise economy and the kinetics of O2 uptake. Due to restrictions in using invasive techniques too directly measure aerobic and anaerobic muscle metabolism at rest or during exercise in children and adolescents, data from indirect measures, such as respiratory gas exchange, blood markers and performance profiles, will be presented. Anaerobic fitness can be described as the ability to support metabolic demands by non-oxidative mechanisms, and is often assessed through high-intensity exercise.
