Science examines Rotor Q-ring (again)

  • by Alex (FastFitnessTips)
  • 17 May, 2017

Study finds no advantage to non-round chainrings

The aim of this independent study was to further investigate the mechanical and metabolic energetics of using Q-Rings during cycling.Ten elite male road cyclists completed 5-min cycling bouts at 80 RPM at 100, 200 and 300 W using a standard circular chainring and 52-tooth Q-Ring set in two positions: ‘#1’ and ‘#5’. Oxygen consumption was converted to metabolic power. Tangential and radial crank forces and crank position were measured using Axis Cranks (SPE, Carole Park, Australia). 

Results? Results suggested no significant differences were found between the chainrings for total metabolic power or the physiological estimate ofinternal mechanical power (IP) 

http://www.jsc-journal.com/ojs/index.php?journal=JSC&page=article&op=view&path%5B%5D=202

Internal Mechanical Power During Cycling Using Non-Circular Versus Circular Chainrings

FastFitness.Tips Blog

by Alex (FastFitnessTips) 17 May, 2017

The aim of this independent study was to further investigate the mechanical and metabolic energetics of using Q-Rings during cycling.Ten elite male road cyclists completed 5-min cycling bouts at 80 RPM at 100, 200 and 300 W using a standard circular chainring and 52-tooth Q-Ring set in two positions: ‘#1’ and ‘#5’. Oxygen consumption was converted to metabolic power. Tangential and radial crank forces and crank position were measured using Axis Cranks (SPE, Carole Park, Australia). 

Results? Results suggested no significant differences were found between the chainrings for total metabolic power or the physiological estimate ofinternal mechanical power (IP) 

http://www.jsc-journal.com/ojs/index.php?journal=JSC&page=article&op=view&path%5B%5D=202

Internal Mechanical Power During Cycling Using Non-Circular Versus Circular Chainrings

by Alex (FastFitnessTips) 17 May, 2017
In this new study researchers examined the claims of ±3% accuracy in power of several KICKR units vs SRM power meter using a first-principles based dynamic calibration rig (CALRIG).Five KICKRs and one SRM unit were assessed by a CALRIG-driven incremental test. Following a 15 min warm-up and ‘calibration’ as per manufacturer instructions, power was increased (starting at 50 W) by 50 W every 2 min up to 400 W. Each unit was tested twice non-consecutively, in random order.

The mean error across all KICKR units was -1.5% (range: -3.1% to 0.0%) compared to -1.6% reported by the SRM. For test-retest reproducibility, two KICKRs had statistically significant changes in mean error, with an average 1.3% change across all KICKRs. Comparatively, the SRM reported a 0.4% change between trials.

The authors conclude that the Wahoo KICKR trainer measures power to a similar level of accuracy to the more reputable SRM power meter during an incremental exercise test but results did weaken at higher power levels. 



( http://www.jsc-journal.com/ojs/index.php?journal=JSC&page=article&op=view&path%5B%5D=240 )
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