INTRODUCTION & AIMS Muscle oxygenation characteristics are suggested to better explain performance than peak oxygen uptake (VO2peak) in highly trained canoe-kayak athletes (Paquette et. al, 2018), but this has not been explored with rowers. Therefore, this investigation aimed to 1) determine whether maximal oxygen extraction improved prediction of rowing ergometer mean maximal power (MMP; W/kg) compared to VO2peak alone, and 2) assess differences in muscle oxygen extraction between anatomical sites during incremental rowing. METHODS Trained male (n=16) and female (n=6) rowers completed a 7x4min graded exercise test on a rowing ergometer to determine mean power output for each stage and VO2peak and MMP during the final stage. Change in muscle oxygen extraction (Delta[HHb]) during each stage was determined using near infrared spectroscopy (NIRS) at the vastus lateralis (VL), gastrocnemius medialis (GM), and biceps brachii (BB). The best predictor of MMP was determined using linear regression, and mixed-effects models were used to assess Delta[HHb] across sites and stage. RESULTS VO2peak was a significant predictor of MMP (R2=0.74); however, Delta[HHb] (at each site individually or combined) had no association with MMP (R2=0.05). The strongest model included VO2peak and GM Delta[HHb] (R2=0.83); however, the improvement in model fit was modest (mean absolute error decreased from 0.211W.kg-1 to 0.193W.kg-1). A significant site x stage interaction was observed for Delta[HHb] at each site across all stages. Post-hoc analysis revealed VL Delta[HHb] was higher than GM Delta[HHb] for each stage; VL Delta[HHb] was lower than BB Delta[HHb] from stages 1-4, then higher from stages 5-7; and GM Delta[HHb] was lower than BB Delta[HHb] for stages 1-6, but higher in the final stage. CONCLUSION Maximal oxygen extraction alone cannot predict ergometer MMP in trained rowers. However, NIRS derived muscle oxygen extraction may provide additional useful information regarding relative muscle contributions at varying exercise intensities.
© Copyright 2024 Journal of Clinical Exercise Physiology. Alle Rechte vorbehalten.