Oxygen uptake kinetics in children and adults after the onset of moderate-intensity exercise

Samantha G Fawkner, Neil Armstrong, Christopher R Potter, Joanne R Welsman

Research output: Contribution to journalArticlepeer-review

Abstract / Description of output

The literature suggests that the oxygen uptake (VO2) response to the onset of moderate-intensity exercise may be both mature from childhood and independent of sex. Yet the cardiorespiratory response to exercise and the metabolic profile of the muscle appear to change with growth and development and to differ between the sexes. The aim of this study was to investigate further changes in the VO2 kinetic response with age and sex. Participants completed a series of no less than four step change transitions, from unloaded pedalling to a constant work rate corresponding to 80% of their previously determined ventilatory threshold. Each participant's breath-by-breath responses were interpolated to 1 s intervals, time aligned and then averaged. A single exponential model that included a time delay was used to analyse the averaged response following phase 1 (15 s). Participants with parameter confidence intervals more than +/- 5 s were removed from the sample; the results for the remaining 13 men and 12 women (age 19-26 years), 12 boys and 11 girls (age 11-12 years) were used for statistical analysis. Children had a significantly shorter time constant than adults, both for males (19.0+/-2.0 and 27.9+/-8.6 s respectively; P0.05). A significant relationship between the time constant and peak VO2 was found only in adult males (P
Original languageEnglish
Pages (from-to)319-26
Number of pages8
JournalJournal of Sports Sciences
Issue number4
Publication statusPublished - 2002


Dive into the research topics of 'Oxygen uptake kinetics in children and adults after the onset of moderate-intensity exercise'. Together they form a unique fingerprint.

Cite this