A simplified strategy for the estimation of the exercise ventilatory thresholds

Area of Science:

• Exercise Physiology
• Sports Science
• Cardiorespiratory Fitness Assessment

Background:

• Exercise ventilatory thresholds (VT1 and VT2) are crucial physiological markers for exercise prescription.
• Traditional methods for estimating VT1 and VT2 rely on cardiopulmonary exercise testing (CPET) using gas exchange and ventilatory variables.
• An alternative, simplified approach using only ventilatory data (ventilometry) may offer a more accessible estimation method.

Purpose of the Study:

• To analyze the agreement between VT1 and VT2 values estimated by standard CPET and a novel ventilometry-based approach.
• To evaluate the reliability and potential utility of ventilometry for determining exercise intensity domains.

Main Methods:

• Forty-two untrained adults underwent maximal incremental cycle ergometry.
• Ventilatory thresholds were determined using conventional CPET methods (e.g., V-slope, ventilatory equivalents) and a simplified ventilometry approach (VE vs. time, VE/time vs. time, breathing frequency vs. time).
• Bland-Altman analysis was employed to assess the agreement between the two methods.

Main Results:

• No significant differences were found between the CPET and ventilometry methods for VT1, VT2, or peak ventilation.
• Bland-Altman analysis showed lower mean bias for VT2 (2 ± 9 bpm) compared to VT1 (0 ± 17 bpm).
• The ventilometry method for VT2 differed by more than 10 bpm from the standard procedure in only 9% of subjects, independent of fitness level.

Conclusions:

• A simplified ventilometry approach provides acceptable estimates of exercise ventilatory thresholds, particularly VT2, during ramp-incremental exercise.
• This method demonstrates potential as a practical tool for exercise training prescription in untrained populations.
• Further research may validate this approach for diverse populations and exercise modalities.