Estimating the parameters of aerobic function during exercise using an exponentially increasing work rate protocol

Area of Science:

• Cardiopulmonary exercise testing
• Exercise physiology

Background:

• The standardized exponential exercise protocol (STEEP) is a novel method for cardiopulmonary exercise testing.
• STEEP aims to accommodate a wide range of exercise capacities with a narrow tolerance time variation.
• Previous comparisons of STEEP focused solely on VO2max, neglecting other key aerobic function parameters.

Purpose of the Study:

• To investigate the feasibility of discerning aerobic function parameters from the STEEP protocol.
• To theoretically and practically assess the estimation of anaerobic threshold (AT), VO2 time constant, and delta VO2/delta WR using STEEP.
• To compare STEEP's parameter estimation with the standard ramp protocol.

Main Methods:

• Theoretical analysis of VO2 time constant and delta VO2/delta WR estimation from STEEP.
• Development of a practical procedure for estimating parameter analogues.
• Comparison of STEEP and ramp protocols in six subjects, measuring VO2max, AT, VO2 time constant, and delta VO2/delta WR.

Main Results:

• Theoretical analysis indicated that VO2 time constant and delta VO2/delta WR cannot be uniquely estimated from STEEP.
• Preliminary results showed strong positive correlations for VO2max and AT-VO2 between STEEP and ramp protocols (r = 0.997 and r = 0.980, respectively).
• Correlations for VO2 time constant and delta VO2/delta WR were not statistically significant between the two protocols.

Conclusions:

• The STEEP protocol appears suitable for estimating VO2max and AT.
• Further theoretical and practical investigation is required to understand and address the discrepancies in estimating VO2 time constant and delta VO2/delta WR.
• The STEEP protocol may require modifications or further validation for comprehensive aerobic function assessment.