Validity and reliability of an alternative method for measuring power output during six second all out cycling

Martin Watson, Daniele Bibbo, Charles R. Duffy, Philip E. Riches, Silvia Conforto, Andrea Macaluso

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)
77 Downloads (Pure)


In a laboratory setting where both a mechanically-braked cycling ergometer and a motion analysis (MA) system are available, flywheel angular displacement can be estimated by using MA. The purpose of this investigation was to assess the validity and reliability of a MA method for measuring maximal power output (Pmax) in comparison with a force transducer (FT) method. Eight males and eight females undertook three identical sessions, separated by 4 to 6 days; the first being a familiarization session. Individuals performed three 6-second sprints against 50% of the maximal resistance to complete two pedal revolutions with a 3-minute rest between trials. Power was determined independently using both MA and FT analyses. Validity: MA recorded significantly higher Pmax than FT (P < .05). Bland-Altman plots showed that there was a systematic bias in the difference between the measures of the two systems. This difference increased as power increased. Repeatability: Intraclass correlation coefficients were on average 0.90 ± 0.05 in males and 0.85 ± 0.08 in females. Measuring Pmax by MA, therefore, is as appropriate for use in exercise physiology research as Pmax measured by FT, provided that a bias between these measurements methods is allowed for.
Original languageEnglish
Pages (from-to)598-603
Number of pages6
JournalJournal of Applied Biomechanics
Issue number4
Early online date30 Jun 2014
Publication statusPublished - Aug 2014


  • power output
  • cycling
  • power measurement
  • motion analysis
  • force transducers
  • flywheel
  • acceleration
  • instrumented pedal


Dive into the research topics of 'Validity and reliability of an alternative method for measuring power output during six second all out cycling'. Together they form a unique fingerprint.

Cite this