Validity and reliability of the Axiom PowerTrain cycle ergometer when compared with an SRM powermeter

Int J Sports Med. 2005 Jan-Feb;26(1):59-65. doi: 10.1055/s-2004-817855.

Abstract

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.

Publication types

  • Clinical Trial
  • Comparative Study
  • Validation Study

MeSH terms

  • Adult
  • Bicycling / physiology*
  • Exercise / physiology
  • Exercise Test*
  • Humans
  • Male
  • Monitoring, Physiologic / instrumentation*
  • Muscle, Skeletal / physiology
  • Reproducibility of Results
  • Sports Medicine / instrumentation*
  • Sports Medicine / methods
  • Task Performance and Analysis*