Purpose We examined the effect of β-blockade on measures and reproducibility of heart rate (HR), oxygen uptake (<InlineEquation ID="IEq1"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="421_2025_5818_Article_IEq1.gif" Format="GIF" Height="20" Rendition="HTML" Resolution="72" Type="Linedraw" Width="32" /> </InlineMediaObject> <EquationSource Format="TEX">${\dot{\rm{V}}}{\rm{O}}_{2}$</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mover accent="true"> <mi mathvariant="normal">V</mi> <mo>˙</mo> </mover> <msub> <mi mathvariant="normal">O</mi> <mn>2</mn> </msub> </mrow> </math></EquationSource> </InlineEquation>) and work rate (WR) across repeated bouts of short-duration, RPE-regulated exercise. Methods Participants completed an RPE-regulated, interval-based exercise session under control and β-blockade conditions with six 3-min bouts alternating between RPE 13 and RPE 15, separated by 2-min active recovery periods. Participants adjusted treadmill speed/grade to meet the target RPE. Linear mixed effects models assessed the effect β-blockade on exercise responses for each RPE, while intraclass correlation coefficients (ICC) and coefficients of variation (CV) evaluated reproducibility across bouts. Results β-Blockade significantly reduced HR (− 36.5 beat min−1, p < 0.001), <InlineEquation ID="IEq2"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="421_2025_5818_Article_IEq1.gif" Format="GIF" Height="20" Rendition="HTML" Resolution="72" Type="Linedraw" Width="32" /> </InlineMediaObject> <EquationSource Format="TEX">${\dot{\rm{V}}}{\rm{O}}_{2}$</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mover accent="true"> <mi mathvariant="normal">V</mi> <mo>˙</mo> </mover> <msub> <mi mathvariant="normal">O</mi> <mn>2</mn> </msub> </mrow> </math></EquationSource> </InlineEquation> (− 4.2 mL kg−1 min−1, p < 0.001) and work rate (− 0.6 METs, p = 0.022) during exercise. Differences between conditions remained significant for %HRpeak (p < 0.001) but not %<InlineEquation ID="IEq3"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="421_2025_5818_Article_IEq3.gif" Format="GIF" Height="18" Rendition="HTML" Resolution="72" Type="Linedraw" Width="14" /> </InlineMediaObject> <EquationSource Format="TEX">${\dot{\rm{V}}}$</EquationSource> <EquationSource Format="MATHML"><math> <mover accent="true"> <mi mathvariant="normal">V</mi> <mo>˙</mo> </mover> </math></EquationSource> </InlineEquation>O2peak or %WRpeak (p > 0.05). Exercise responses were consistently higher at RPE 15 than RPE 13 (all p < 0.001). A significant interaction showed greater HR reduction at RPE 15 (45.5 beat min−1) than RPE 13 (40.0 beat min−1) under β-blockade (p = 0.041). ICC values indicated good to excellent reproducibility across bouts, with no significant difference between conditions. Variability across bouts was low (mean CV = 2–8%) and unaffected by β-blockade. Conclusion Our findings suggest that despite significant reductions in absolute responses, β-blockade does not affect relative measures of <InlineEquation ID="IEq4"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="421_2025_5818_Article_IEq3.gif" Format="GIF" Height="18" Rendition="HTML" Resolution="72" Type="Linedraw" Width="14" /> </InlineMediaObject> <EquationSource Format="TEX">${\dot{\rm{V}}}$</EquationSource> <EquationSource Format="MATHML"><math> <mover accent="true"> <mi mathvariant="normal">V</mi> <mo>˙</mo> </mover> </math></EquationSource> </InlineEquation>O2 or work rate. RPE-regulated exercise may facilitate highly reproducible exercise intensities, making it particularly valuable for populations where β-blocker use is prevalent.

Effect of β-blockade on measures and reproducibility of heart rate, oxygen uptake and work rate across repeated bouts of short-duration, RPE-regulated exercise

期刊论文
出版模式：

开放获取
发表日期：

2025年6月1日

查看全文

Braden L. Mitchell,
Kade Davison,
Gaynor Parfitt,
Roger G. Eston

摘要

Purpose

We examined the effect of β-blockade on measures and reproducibility of heart rate (HR), oxygen uptake ( ${\dot{\rm{V}}}{\rm{O}}_{2}$ $\dot{V} O_{2}$ ) and work rate (WR) across repeated bouts of short-duration, RPE-regulated exercise.

Methods

Participants completed an RPE-regulated, interval-based exercise session under control and β-blockade conditions with six 3-min bouts alternating between RPE 13 and RPE 15, separated by 2-min active recovery periods. Participants adjusted treadmill speed/grade to meet the target RPE. Linear mixed effects models assessed the effect β-blockade on exercise responses for each RPE, while intraclass correlation coefficients (ICC) and coefficients of variation (CV) evaluated reproducibility across bouts.

Results

β-Blockade significantly reduced HR (− 36.5 beat min⁻¹, p < 0.001), ${\dot{\rm{V}}}{\rm{O}}_{2}$ $\dot{V} O_{2}$ (− 4.2 mL kg⁻¹ min⁻¹, p < 0.001) and work rate (− 0.6 METs, p = 0.022) during exercise. Differences between conditions remained significant for %HR_peak (p < 0.001) but not % ${\dot{\rm{V}}}$ $\dot{V}$ O_2peak or %WR_peak (p > 0.05). Exercise responses were consistently higher at RPE 15 than RPE 13 (all p < 0.001). A significant interaction showed greater HR reduction at RPE 15 (45.5 beat min⁻¹) than RPE 13 (40.0 beat min⁻¹) under β-blockade (p = 0.041). ICC values indicated good to excellent reproducibility across bouts, with no significant difference between conditions. Variability across bouts was low (mean CV = 2–8%) and unaffected by β-blockade.

Conclusion

Our findings suggest that despite significant reductions in absolute responses, β-blockade does not affect relative measures of ${\dot{\rm{V}}}$ $\dot{V}$ O₂ or work rate. RPE-regulated exercise may facilitate highly reproducible exercise intensities, making it particularly valuable for populations where β-blocker use is prevalent.