Erin Calaine Inglis1, Danilo Iannetta1, Juan M Murias2. 1. Faculty of Kinesiology, University of Calgary, KNB 434, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada. 2. Faculty of Kinesiology, University of Calgary, KNB 434, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada. jmmurias@ucalgary.ca.
Abstract
PURPOSE: This study evaluated (i) the relationship between oxygen uptake ([Formula: see text]O2) kinetics and maximal [Formula: see text]O2 ([Formula: see text]O2max) within groups differing in fitness status, and (ii) the adjustment of [Formula: see text]O2 kinetics compared to that of central [cardiac output (Q̇), heart rate (HR)] and peripheral (deoxyhemoglobin over [Formula: see text]O2 ratio ([HHb]/[Formula: see text]O2)] O2 delivery, during step-transitions to moderate-intensity exercise. METHODS: Thirty-six young healthy male participants (18 untrained; 18 trained) performed a ramp-incremental test to exhaustion and 3 step-transitions to moderate-intensity exercise. Q̇ and HR kinetics were measured in 18 participants (9 untrained; 9 trained). RESULTS: No significant correlation between τ̇[Formula: see text]O2 and [Formula: see text]O2max was found in trained participants (r = 0.29; p > 0.05) whereas a significant negative correlation was found in untrained (r = - 0.58; p < 0.05) and all participants (r = - 0.82; p < 0.05). τQ̇ (18.8 ± 5.5 s) and τHR (20.1 ± 6.2 s) were significantly greater than τ[Formula: see text]O2 (13.9 ± 2.7 s) for trained (p < 0.05). No differences were found between τQ̇ (22.8 ± 8.45 s), τHR (21.2 ± 8.3 s) and τ[Formula: see text]O2 (28.9 ± 5.7 s) for untrained (p > 0.05). τQ̇ demonstrated a significant strong positive correlation with τHR in trained (r = 0.76; p < 0.05) but not untrained (r = 0.61; p > 0.05). A significant overshoot in the [HHb]/[Formula: see text]O2 ratio was found in the untrained groups (p < 0.05) but not in the trained groups (p > 0.05) CONCLUSION: The results indicated that when comparing participants of different fitness status (i) there is a point at which greater V̇O2max values are not accompanied by faster [Formula: see text]O2 kinetics; (ii) central delivery of O2 does not seem to limit the kinetics of [Formula: see text]O2; and (iii) O2 delivery within the active tissues might contribute to the slower [Formula: see text]O2 kinetics response in untrained participants.
PURPOSE: This study evaluated (i) the relationship between oxygen uptake ([Formula: see text]O2) kinetics and maximal [Formula: see text]O2 ([Formula: see text]O2max) within groups differing in fitness status, and (ii) the adjustment of [Formula: see text]O2 kinetics compared to that of central [cardiac output (Q̇), heart rate (HR)] and peripheral (deoxyhemoglobin over [Formula: see text]O2 ratio ([HHb]/[Formula: see text]O2)] O2 delivery, during step-transitions to moderate-intensity exercise. METHODS: Thirty-six young healthy male participants (18 untrained; 18 trained) performed a ramp-incremental test to exhaustion and 3 step-transitions to moderate-intensity exercise. Q̇ and HR kinetics were measured in 18 participants (9 untrained; 9 trained). RESULTS: No significant correlation between τ̇[Formula: see text]O2 and [Formula: see text]O2max was found in trained participants (r = 0.29; p > 0.05) whereas a significant negative correlation was found in untrained (r = - 0.58; p < 0.05) and all participants (r = - 0.82; p < 0.05). τQ̇ (18.8 ± 5.5 s) and τHR (20.1 ± 6.2 s) were significantly greater than τ[Formula: see text]O2 (13.9 ± 2.7 s) for trained (p < 0.05). No differences were found between τQ̇ (22.8 ± 8.45 s), τHR (21.2 ± 8.3 s) and τ[Formula: see text]O2 (28.9 ± 5.7 s) for untrained (p > 0.05). τQ̇ demonstrated a significant strong positive correlation with τHR in trained (r = 0.76; p < 0.05) but not untrained (r = 0.61; p > 0.05). A significant overshoot in the [HHb]/[Formula: see text]O2 ratio was found in the untrained groups (p < 0.05) but not in the trained groups (p > 0.05) CONCLUSION: The results indicated that when comparing participants of different fitness status (i) there is a point at which greater V̇O2max values are not accompanied by faster [Formula: see text]O2 kinetics; (ii) central delivery of O2 does not seem to limit the kinetics of [Formula: see text]O2; and (iii) O2 delivery within the active tissues might contribute to the slower [Formula: see text]O2 kinetics response in untrained participants.
Authors: Bruno Grassi; Harry B Rossiter; Michael C Hogan; Richard A Howlett; James E Harris; Matthew L Goodwin; John L Dobson; L Bruce Gladden Journal: J Physiol Date: 2010-11-08 Impact factor: 5.182
Authors: Kevin De Pauw; Bart Roelands; Stephen S Cheung; Bas de Geus; Gerard Rietjens; Romain Meeusen Journal: Int J Sports Physiol Perform Date: 2013-03 Impact factor: 4.010
Authors: Jayson R Gifford; Ryan S Garten; Ashley D Nelson; Joel D Trinity; Gwenael Layec; Melissa A H Witman; Joshua C Weavil; Tyler Mangum; Corey Hart; Cory Etheredge; Jake Jessop; Amber Bledsoe; David E Morgan; D Walter Wray; Matthew J Rossman; Russell S Richardson Journal: J Physiol Date: 2016-01-19 Impact factor: 5.182
Authors: David C Poole; Leonardo F Ferreira; Brad J Behnke; Thomas J Barstow; Andrew M Jones Journal: Exerc Sport Sci Rev Date: 2007-10 Impact factor: 6.230
Authors: Tyler M Grey; Matthew D Spencer; Glen R Belfry; John M Kowalchuk; Donald H Paterson; Juan M Murias Journal: Med Sci Sports Exerc Date: 2015-02 Impact factor: 5.411
Authors: Alessio Del Torto; Carlo Capelli; Roberto Peressutti; Adriana Di Silvestre; Ugolino Livi; Chiara Nalli; Sandro Sponga; Giampaolo Amici; Umberto Baccarani; Stefano Lazzer Journal: Int J Environ Res Public Health Date: 2022-07-26 Impact factor: 4.614
Authors: Igor Longobardi; Danilo Marcelo Leite do Prado; Karla Fabiana Goessler; Matheus Molina Meletti; Gersiel Nascimento de Oliveira Júnior; Danieli Castro Oliveira de Andrade; Bruno Gualano; Hamilton Roschel Journal: Am J Physiol Heart Circ Physiol Date: 2022-08-19 Impact factor: 5.125