Twenty-five girls and 25 boys (mean age 9.7 ± 0.3 years) each completed a 20- and 30-s Wingate Anaerobic Test (WAnT). Oxygen uptake during the WAnTs, and postexercise blood lactate samples were obtained. Inertia and load-adjusted power variables were higher (18.6–20.1% for peak, and 6.7–7.5% for mean power outputs, p < .05) than the unadjusted values for both the 20- and 30-s WAnTs. The adjusted peak power values were higher (7.7–11.6%, p < .05) in both WAnTs when integrated over 1-s than over 5-s time periods. The aerobic contributions to the tests were lower (p < .05) in the 20-s WAnT (13.7–35.7%) than in the 30-s WAnT (17.7–44.3%) for assumed mechanical efficiencies of 13% and 30%. Postexercise blood lactate concentration after the WAnTs peaked by 2 min. No gender differences (p > .05) in anaerobic performances or peak blood lactate values were detected.
Michael Chia, Neil Armstrong, and David Childs are with the Children’s Health & Exercise Research Centre, School of Education, University of Exeter, Heavitree Road, Exeter, EX1 2LU, United Kingdom.