The talk test"s responsiveness to an 8-week exercise-training program in cardiovascular disease patients

Funding Acknowledgements Type of funding sources: None. Background Talk test (TT) is an alternative and accessible tool for prescribing and monitoring aerobic training intensity. Although the TT is reliable and valid for cardiorespiratory assessment, its responsiveness to exercise training remains unexplored. Purpose To evaluate the responsiveness of TT in cardiovascular disease (CVD) patients who underwent an exercise training program. Methods Twenty-one CVD patients (61.7 ± 8.4 years) performed an exercise-training program on phase II of cardiac rehabilitation (45-min 3-times a week). The six-minute walk test (6MWT) and TT were done to assess functional capacity at baseline and after 8 weeks. In the individualized TT the treadmill’s speed and/or grade were increased every 2-min, with speed changes based on a reference equation for the 6MWT distance (6MWD). The subjects were asked to read a 38 words standard paragraph at the last 30s of each stage and to answer if they could talk comfortably. Answer options were i) YES (TT+), ii) UNCERTAIN (TT±), or iii) NO (TT-). The first ventilatory threshold (VT1) was identified by two reviewers using the heart rate variability analysis. A paired t-test was applied to analyze the TT duration and 6MWD. The VT1 and TT workload were analyzed by the Wilcoxon test. Spearman correlation was adopted to compare the TT± and VT1 stages. Results Improvement in the VT1 (2.9 ± 1.2 vs 4.4 ± 1.4 min; p < 0.001), duration (12.1 ± 4.4 vs 14.9 ± 5.2 min; p < 0.001), workload at TT- (67.8 ± 48.4 vs 104.5 ± 65.9 w; p < 0.001), and in the 6MWD (471.5 ± 100.3 vs 533.7 ± 92.9 m; p < 0.001) were observed. There was strong correlation between TT± and VT1 in pre (r = 0.613; p < 0.05) and post-rehabilitation (r = 0.678; p < 0.05). Conclusion Talk test performed on a treadmill showed responsiveness after eight weeks of exercise training, being sensitive to the physiological changes provided by the rehabilitation program in CVD patients.