Int J Sports Med 2005; 26(1/02): 59-65
DOI: 10.1055/s-2004-817855
Training & Testing

© Georg Thieme Verlag KG Stuttgart · New York

Validity and Reliability of the Axiom Powertrain Cycle Ergometer When Compared with an SRM Powermeter

W. Bertucci1 , S. Duc1 , V. Villerius1 , F. Grappe1
  • 1Laboratoire de Mécanique Appliquée (U.M.R. C.N.R.S. 6604), Université de Franche Comté, Besançon, France
Further Information

Publication History

Accepted after revision: January 6, 2004

Publication Date:
30 July 2004 (online)


The purpose of this study was to determine the validity and the reliability of a stationary electromagnetically-braked cycle ergometer (Axiom PowerTrain) against the SRM power measuring crankset. Nineteen male competitive cyclists completed four tests on their bicycle equipped with a 20-strain gauges SRM crankset: a maximal aerobic power (MAP) test and three 10-min time trials (TTs) with three different simulated slopes (0, 3, and 6 %). The Axiom ergometer overestimated (p < 0.05) the SRM power output during the last stage of the MAP test and during TTs, by 5 % and 12 %, respectively. Power output (PO) of the Axiom ergometer drifted significantly (p < 0.05) with the time during TT. These findings indicate that the Axiom ergometer does not provide a valid measure of PO compared with SRM. However, the small coefficient of variation (2.2 %) during the MAP test indicates that the Axiom provides a reliable PO and that it can be used e.g. for relative PO comparisons with competitive cyclists during a race season.


W. Bertucci

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