Does arterial health affect VO₂ₚₑₐₖ and muscle oxygenation in a sedentary cohort?

Abstract

Purpose: An association between arterial health and peak oxygen consumption (VO₂ₚₑₐₖ) has been demonstrated; however, little is known about how arterial health influences muscular oxygenation during exercise. The aim of this study was to gain insight into the relations between arterial health, VO₂ₚₑₐₖ, and muscle oxygenation in a middle-age sedentary population. Methods: Radial augmentation index (AIx) (via pulse wave analysis) of 21 sedentary middle-age participants (15 females and six males; age, 54.7 ± 5.4; body mass index, 29.0 ± 4.7 kg·m⁻²; mean ± SD) was assessed, and on another day ( < 7 d), participants completed a modified Bruce protocol (MBP). Using near-infrared spectroscopy, total oxygenation index (TOI) of the left flexor carpi ulnaris and the left vastus lateralis were monitored throughout the MBP. Independent and average (arm + leg) percentage decrease in TOI between stage 1 of the MBP and maximal exertion (TOI diff) during MBP was calculated. Changes between dependent variables were correlated using Pearson product-moment correlations and were interpreted as follows: r > 0.5, strong; 0.5 > r > 0.3, moderate; and r < 0.3, weak. Results: We observed moderate negative correlation between AIx and VO₂ₚₑₐₖ (r = -0.34, -0.63 to -0.03; Pearson correlation, 90% confidence limits) and strong negative correlation between AIx and average TOI diff (r = -0.58, -0.78 to -0.27). The VO₂ₚₑₐₖ and average TOI diff were strongly correlated (r = 0.55, 0.23-0.77). Conclusions: Arterial health seems to be an important determinant of muscle oxygenation during exercise. In turn, muscle oxygenation during exercise is strongly related to VO₂ₚₑₐₖ. Developing training modalities to prioritize arterial health outcomes may be a useful way of improving VO₂ₚₑₐₖ in this population.