Rationale: The last intensity at which a person can comfortably speak, the Talk Test (TT) is a subjective method used to guide exercise training intensity. The TT has been shown to relate well to objective measures of intensity such as ventilatory threshold (VT) and can be applied to both healthy and clinical populations. However, most studies comparing VT and TT have been correlative instead of interventional.

Objectives: This study was designed to experimentally test the hypothesis that TT results would improve as VT improved following exercise training.

Methods: Healthy sedentary volunteers (N = 15) exercised maximally on a treadmill to define VT and Vo₂max and the occurrence of the last positive stage of the TT (LPTT). Over the next 6 weeks, a training protocol based on ACSM guidelines was followed before again measuring the criterion variables.

Results: Training resulted in a significant improvement (P < .01) in the treadmill duration at the last positive stage of the TT (9.9 +/- 2.6 to 11.9 +/- 2.7 minutes), in VT (23.7 +/- 6.4 to 28.4 +/- 9.2 mL min^-1 kg^-1), and in Vo₂max (37.6 +/- 9.2 to 41.7 +/- 10.2 mL min^-1 kg^-1). Improvements in performance at the last positive stage of the TT were reflected in both HR (147 +/-17 to 160 +/- 13 bpm) and RPE (3.4 +/- 0.9 to 4.1 +/- 0.9).

Conclusion: Significant improvement in the VT was well reflected by increases in the time to the last positive stage of the TT. This finding supports the experimental hypothesis, is consistent with our earlier work showing reductions in VT and TT with blood donation, supports a causal relationship between VT and TT, and supports the use of the TT as a subjective criterion for exercise prescription.