Assessing the Exercise Intensity of Patients With Cardiovascular Disease: Development and Validation of a Treadmill Talk Test Protocol.

Abstract

Purpose: To validate a treadmill talk test (TT) protocol based on the 6-minute walk test predicted average speed (6MWS) to evaluate exercise intensity in adults with cardiovascular disease (CVD).

Methods: A cardiopulmonary exercise test was performed on the first day. Two TT were performed on different days. The initial workload (WL) of the proposed TT protocol (treadmill TT protocol based on 6MWS [TT-T6M]) was set at a 2% incline and 70% of the 6MWS. Speed or grade was increased at each subsequent 2-minute stage. Participants recited a paragraph during the final 30 seconds of each stage and were asked if they could speak comfortably. They could respond "yes" (TT+), "uncertain" (TT±), or "no" (TT-). To determine validity, heart rate and WL were collected at ventilatory thresholds (VT) and TT stages, and then correlated using the Pearson or Spearman correlation coefficient. Test-retest, intrarater, and interrater reliability were assessed using the intraclass correlation coefficient (ICC 2,1 ), with TT stages and total time as variables.

Results: Twenty-five patients with CVD (15 men, 60 ± 8 years) were included. Test reliability was excellent (ICC 2,1 = .86), with no difference in test-retest duration. The heart rate and WL values were similar between VT1 and the last TT+ stage and between VT2 and the TT- stage. Intrarater and interrater agreements for the speech comfort assessment were also excellent (ICC 2,1 > .90).

Conclusions: The treadmill TT protocol based on 6MWS is valid, reproducible, and reliable. It can be used to evaluate, prescribe, and monitor the exercise intensity zone, which occurs between the last TT+ and TT- stages, for individuals with CVD.