An Intensity-dependent Slow Component of HR Interferes with Accurate Exercise Implementation in Postmenopausal Women

Purpose We tested the hypothesis that a slow component of HR (i.e., scHR) occurs in all intensity domains, greater than the slow component of oxygen uptake (scV˙O2), and we developed an equation to predict it across exercise intensities. Method Eighteen healthy, postmenopausal women (54 ± 4 yr) performed on a cycle ergometer: i) a ramp incremental test for thresholds and V˙O2max detection; ii) 30-min constant work exercise at 40%, 50%, 60%, 70%, and 80% V˙O2max for the measurement of scHR, scV˙O2, stroke volume, and body temperature (T°). scHR and scV˙O2 were compared by two-way repeated-measures ANOVA (intensity and variable). Pearson correlation was calculated between the slow component of all variables, relative intensity, and domain. scHR (in beats per minute) was predicted with a linear model based on exercise intensity relative to the respiratory compensation point (RCP). Results A positive scHR was present in all domains, twice the size of scV̇O2 (P
Source: Medicine and Science in Sports and Exercise - Category: Sports Medicine Tags: APPLIED SCIENCES Source Type: research