Although the company stopped producing the CT in 2017, this resistance trainer is still widely used ( Dionne et al., 2018 Nieman et al., 2018a, b RГёnnestad et al., 2018 Silva-Cavalcante et al., 2018, 2019 Ely et al., 2019 Evens and Danoff, 2019 Chidnok et al., 2020 Haugen et al., 2020) and will likely be used for several more years by research teams all around the world, included ours ( Jeker et al., 2020 Claveau et al., 2021), for several reasons. It has been used for research purposes to measure cycling TT performances ( van Essen and Gibala, 2006 Berardi et al., 2008 Cermak et al., 2012 Wilkerson et al., 2012 Dyer and McKune, 2013 Lamberts, 2014 Nieman et al., 2015 Peveler et al., 2017 Adams et al., 2019 Ely et al., 2019 Perreault-Briere et al., 2019), TT's reliability ( Lamberts et al., 2009 Sparks et al., 2016) or analyze pacing strategies during TTs ( Atkinson and Brunskill, 2000 Micklewright et al., 2010 Jones et al., 2015 Jones and Williams, 2017 Whitehead et al., 2018). The Computrainer в„ў (CT, RacerMate, Seattle, WA, USA) is an electromagnetically braked resistance trainer applying friction to the rear wheel of a standard bike, which can be used in a cadence dependent and independent mode. Cycling TTs can easily be performed in a controlled research environment using a cycling ergometer, although their ecological validity will be substantially enhanced if research participants use their own bike on a resistance trainer. Unarguably, however, their ecological validity is greater than cycling tests during which workloads are being dictated, making them a premier choice for scientists aiming to optimize the external validity of their research findings. Although debatable ( Amann et al., 2008), they have been demonstrated to be more reliable than either fixed-intensity ( Jeukendrup et al., 1996) or incremental cycling tests to exhaustion ( Coakley and Passfield, 2018). In conclusion, using 40 and 100 km TTs containing 1 or 4 km bursts in power output, the present results indicate that (1) the CT can reliably be used by scientists to determine differences between research interventions (2) the CT provides valid results of power output when data are being analyzed as a whole to derive one mean value of power output and (3) variations in workload make it difficult to determine at any one time the veracity of the true power output produced by the athlete.Д¬ycling time-trials (TTs) are being used under controlled research settings to assess the effect of an intervention or condition on endurance performance. Average biases between repeated trials were contained within В± 1.1% for both TTs. However, measurement errors were dependent upon the workload variations, fluctuating from 0.2 to 5.1%. For the 40 and 100 km TTs, cluster-based analyses revealed a mean measurement error from the true workload of respectively 0.7 and 0.9%. The load patterns imposed by the CT were designed from previously published studies in trained cyclists and included multiple 1 or 4 km bursts in power output. The validity and reliability of the Computrainer Lab в„ў (CT) was assessed, for the first time, using a high-precision motor-driven calibration rig during simulated variable intensity 40 and 100 km time-trials (TTs). 3Research Centre on Aging, University of Sherbrooke, Sherbrooke, QC, Canada.2VГ‰LUS Laboratory, Department of Mechanical Engineering, University of Sherbrooke, Sherbrooke, QC, Canada.1Department of Kinanthropology, Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC, Canada.David Jeker 1, Jonathan Gosselin 1, Jean-Marc Drouet 2 and Eric D.

Computrainer power