title: Comparison of oxygen consumption in rats during uphill (concentric) and downhill (eccentric) treadmill exercise tests.
abstract: The study of the physiological adaptations of skeletal muscle in response to eccentric (ECC) contraction is based on protocols in which exercise intensities are determined relative to the concentric (CON) reference exercise (as percentage of the CON maximal oxygen consumption, or VO2max). In order to use similar exercise protocols in rats, we compared the VO2 values during uphill (CON) and downhill (ECC) running tests. VO2 was measured in 15 Wistar rats during incremental treadmill running exercises with different slopes: level (0%), positive (+15% incline: CON+15%) and negative (i15% incline: ECC-15%; and 130% incline: ECC-30%). Similar VO2 values were obtained in the ECC-30% and CON+15% running conditions at the three target speeds (15, 25 and 35 cm/sec). Conversely, VO2 values were lower (p < 0.05) in the ECC-15% than in the CON+15% condition (CON+15% VO2/ECC-15% VO2 ratios ranging from 1.86 to 2.05 at the three target speeds). Thus, doubling the downhill slope gradient in ECC condition leads to an oxygen consumption level that is not significantly different as in CON condition. These findings can be useful for designing animal research protocols to study the effects of ECC and CON exercise in ageing population or subjects suffering from cardiovascular diseases. Key PointsVO2 in rats during treadmill race in eccentric and concentric conditions were measured.A novel breath-by-breath device allowing direct access to the animal was used.THREE DIFFERENT SLOPES: +15%, -15% and -30% were used.VO2 values obtained in the -30% eccentric and the +15% concentric conditions were not significantly different.
authors.affiliation: Clermont Université, Université Blaise Pascal, Laboratoire des Adaptations Métaboliques à l'Exercice en conditions Physiologiques et Pathologiques (AME2P) , Aubière Cedex, France.
authors.forename: Vivien
authors.initials: V
authors.lastname: Chavanelle
authors.affiliation: Clermont Université, Université Blaise Pascal, Laboratoire des Adaptations Métaboliques à l'Exercice en conditions Physiologiques et Pathologiques (AME2P) , Aubière Cedex, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Sirvent
authors.affiliation: Clermont Université, Université Blaise Pascal, Laboratoire des Adaptations Métaboliques à l'Exercice en conditions Physiologiques et Pathologiques (AME2P) , Aubière Cedex, France.
authors.forename: Gaël
authors.initials: G
authors.lastname: Ennequin
authors.affiliation: Clermont Université, Université Blaise Pascal, Laboratoire des Adaptations Métaboliques à l'Exercice en conditions Physiologiques et Pathologiques (AME2P) , Aubière Cedex, France.
authors.forename: Kévin
authors.initials: K
authors.lastname: Caillaud
authors.affiliation: INRA, UMR 1019, CRNH-Auvergne , Clermont-Ferrand, 1 France ; UFR Médecine , Clermont-Ferrand, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Montaurier
authors.affiliation: INRA, UMR 1019, CRNH-Auvergne , Clermont-Ferrand, 1 France ; UFR Médecine , Clermont-Ferrand, France.
authors.forename: Béatrice
authors.initials: B
authors.lastname: Morio
authors.affiliation: Clermont Université, Université Blaise Pascal, Laboratoire des Adaptations Métaboliques à l'Exercice en conditions Physiologiques et Pathologiques (AME2P) , Aubière Cedex, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Boisseau
authors.affiliation: INRA, UMR 1019, CRNH-Auvergne , Clermont-Ferrand, 1 France ; UFR Médecine , Clermont-Ferrand, France ; Department of Sport Medicine and Functional Explorations, University-Hospital (CHU), Hôpital G. Montpied , Clermont-Ferrand, France.
authors.forename: Ruddy
authors.initials: R
authors.lastname: Richard
keywords: Exercise; VO2; eccentric; rodent; running