Research article - (2014)13, 410 - 416
Physiological Responses during Cycling With Oval Chainrings (Q-Ring) and Circular Chainrings
Alfredo Cordova1, Iban Latasa2, Jesus Seco3, Gerardo Villa4, Javier Rodriguez-Falces2,
1Department of Physiology and Biochemistry, University of Valladolid, Soria, Spain
2Department of Electrical and Electronical Engineering, Public University of Navarra, Pamplona, Spain
3Department of Nursing and Physical Therapy, University of Leon, Leon, Spain
4Department of Physical Education, University of Leon, Leon, Spain

Javier Rodriguez-Falces
✉ Universidad Pública de Navarra D.I.E.E., Departament of Electrical and Electronical Engineering, Campus de Arrosadía s/n. 31006 Pamplona, Spain
Email: javier.rodriguez.falces@gmail.com
Received: 10-09-2014 -- Accepted: 03-02-2014
Published (online): 01-05-2014

ABSTRACT

The aim of this study was to compare the physiological responses of cyclists using round (C-ring) or oval (Q-ring) chainrings during an incremental test until exhaustion. Following a randomized design, fourteen male elite cyclists [age (mean ± SD): 21.1 ± 2.1 yr; VO2max: 78.5 ± 5.3 mL·kg-1min-1] performed two incremental maximal tests separated by 48 h (one with C-rings, the other with Q-rings). Starting at 100 W, the workload was increased by 25 W every 3 min until volitional exhaustion. Maximal heart rate, power output and oxygen consumption were compared. Blood lactate was monitored throughout the test. After the incremental test, 4 intermittent 20-s maximal sprints with a 60-s recovery period in between were performed. Maximal isometric voluntary contractions were performed at rest and immediately after each 20-s maximal sprint, and the force and EMG RMS amplitude were recorded from the vastus medialis and vastus lateralis muscles. For the incremental exercise test, no significant differences were found in the maximal power output (P=0.12), oxygen consumption (P=0.39), and heart rate (P=0.32) between Q-rings and C-rings. Throughout the incremental test, lactate levels were comparable when using both the C-rings and Q-rings (P=0.47). During the short sprints, power output was 2.5–6.5% greater for Q-rings than for C-rings (P=0.22). The decline in EMG RMS amplitude observed during the incremental tests was comparable for Q-rings and C-rings (0.42). These findings indicate that the oval chainring design, presented here as “Q-rings”, did not significantly influence the physiological response to an incremental exercise test as compared to a conventional chainring.

Key words: Pedaling, chainring, blood lactate, fatigue, biomechanics

Key Points
  • During the incremental exercise test, no significant differences were found in power output, oxygen consumption or heart rate between oval “Q-rings” and conventional chainrings.
  • Over the course of the incremental test, blood lactate levels were comparable for the oval “Q-rings” and conventional chainrings.
  • During the short sprints performed after the incremental test, there were no statistical differences in power production between oval “Q-rings” and conventional chainrings.








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