Affiliations: [a] Equipe P.P.E.H., Département STAPS,
Université de Saint Etienne, France | [b] Centre de Recherche et d'Innovation sur le Sport
(CRIS), UFR-STAPS, Université Claude Bernard Lyon I, France | [c] Institut für Sport und Sportwissenschaft,
Universität Freiburg, Germany
Note: [] Address for correspondence: Guillaume Mornieux, Médecine
du Sport et Myologie, Hôpital Bellevue – CHU Saint Etienne, 42055
Saint-Etienne Cedex 2, France. Tel.: +33 4 77 12 79 85; Fax: +33 4 77 12 72 29;
E-mail: guillaume.mornieux@univ-st-etienne.fr
Abstract: The aim of this study was to determine if inter-individual
differences in crank torque production and/or pedalling effectiveness influence
the variations of muscular efficiency observed among subjects in cycling.
Eleven subjects performed a 5 minutes steady state cycling at 160 Watts at 80
revolutions per minute. Gross (GE) and net (NE) muscular efficiency, angular
impulses and pedalling effectiveness during the whole pedal revolution
(IE_{360}) and during the downstroke phase
(IE_{180}) were investigated. Angular impulses were not
related to either �O_2 or the muscular efficiency.
IE_{360} was not correlated with either
�O_2 or muscular efficiencies, while
IE_{180} was significantly negatively correlated with
�O_2 (r^2=0.51) and positively
related with NE (r^2 =0.49). The inter-individual
differences in crank torque production, as investigated by angular impulse
values, did not explain inter-individual differences in muscular efficiency.
The lack of relationships between �O_2 or muscular
efficiencies and IE_{360} could be due to the fact that
IE_{360} is equally influenced by both low and high pedal
forces produced during the upstroke and downstroke phases, respectively, while
metabolic energy is mainly consumed during high pedal forces of the downstroke
phase. Finally, when measured during the downstroke phase, inter-individual
differences in pedalling effectiveness could partly be related to the
variations of muscular efficiency observed among subjects in cycling.
