Effects of exercise mode on the oxygen uptake kinetic response to severe-intensity exercise in prepubertal children

The objective of this study was to verify the effect of the exercise mode on slow component of VO2 (VO2SC) in children aged 11-12 years during severe-intensity exercise. After determination of the lactate threshold (LT) and peak VO2 (VO2peak) in both cycling (CE) and running exercise (TR), fourteen active boys completed a series of square-wave transitions of 6-min duration at 75%Δ [75%Δ = LT + 0.75 x (VO2peak-LT)] to determine the VO2 kinetics. The VO2SC was significantly higher in CE (180.5 ± 155.8 ml·min-1) than in TR (113.0 ± 84.2 ml·min -1). We can conclude that, although a VO2SC does indeed develop during TR in children, its magnitude is considerably lower than in CE during severe-intensity exercise. © 2009 Human Kinetics, Inc.