Estimation and performance evaluation of Speed-to-MET conversion methods using the 6-Minute Walk Distance.

Area of Science:

• Exercise Physiology
• Clinical Assessment
• Biostatistics

Background:

• Metabolic Equivalent of Task (MET) quantifies exercise intensity and functional capacity.
• Current MET estimation methods often rely on direct oxygen consumption (VO2) or treadmill-based formulas.
• The 6-Minute Walk Distance (6MWD) is a widely used clinical test, but lacks a precise MET estimation model.

Purpose of the Study:

• To evaluate existing formulas for estimating MET from 6MWD.
• To develop and validate a novel, nonlinear regression model for MET estimation based on 6MWD.
• To create a practical conversion tool for clinical application.

Main Methods:

• Analysis of established American College of Sports Medicine (ACSM) formulas.
• Development of a nonlinear regression model using empirical VO2 data and walking distance.
• Validation of the model against physiological plausibility and existing data.
• Creation of a MET value conversion table for 6MWD results (100-800 meters).

Main Results:

• Existing MET estimation formulas showed limited accuracy, especially at longer distances.
• The proposed nonlinear model effectively captures the relationship between walking distance and energy expenditure.
• The new model allows for accurate MET assignment based on 6MWD without requiring VO2 measurements.

Conclusions:

• The developed nonlinear model offers a more precise method for estimating MET from 6MWD compared to current formulas.
• This tool can aid in patient qualification for rehabilitation and personalized training.
• Improved clinical decision-making and study comparability are expected outcomes.