Stroke volume responses may be related to the gap between peak and maximal O2 consumption

BACKGROUND: Although several studies have focused on maximal O2 uptake (VO2max) measured by a verification phase following the determination of peak O2 uptake ( VO2peak) by a graded exercise test, an explanation for the underlying mechanisms of the difference between VO2peak and confirmed VO2max is scant. OBJECTIVE: To explore the hypothesis that when the difference between VO2peak and VO2max (VO2) increases, the gap between peak stroke volume (SVpeak) and SV level corresponding to .V O2peak velocities (?SV) grows. METHODS: Nine moderately to well-trained male athletes (VO2max: 60.2 ± 7 mL. min-1 . kg-1) volunteered to take part in the study. Following familiarization session, volunteers were asked to perform submaximal and maximal graded exercise tests. Then, constant-loading SVpeak tests (using wattages in a range from 40.100% of .V O2peak) and verification phase (using wattages corresponding with 100.110% of .V O2peak) were conducted in a climatic chamber. RESULTS: The ?VO2 was well correlated with ?SV (Pearson r = 0.89; p ? 0.001). The mean SVpeak of participants corresponded to 60.3 ± 18% of VO2peak.VO2max was significantly greater (11.2%) than VO2peak (60.2 ± 7 vs. 54.2 ± 8.1 mL . min-1 . kg-1) (p ? 0.01). CONCLUSIONS: VO2peak and VO2max differences may be related to the gap between SVpeak and SV at VO2peak. © 2016 IOS Press and the authors. All rights reserved.Ege Üniversitesi Firat University Scientific Research Projects Management Unit: EGE.ETK.2012.13-3.1/1The present study was financially supported by Ege University, Scientific Research Projects Fund (EGE.ETK.2012.13-3.1/1; EGE.BAP.12.005). -