[Obtaining a formula that improves maximum oxygen consumption estimation in cycle ergometer exercise tests].

Area of Science:

• Cardiology
• Exercise Physiology
• Diagnostic Imaging

Background:

• Maximal oxygen consumption (MO2C) is a key indicator of cardiorespiratory fitness.
• Metabolic equivalents (METs) are commonly used to express exercise intensity.
• Standard tables for estimating METs exist, but their accuracy in specific populations needs evaluation.

Purpose of the Study:

• To assess the reliability of the Spanish Society of Cardiology's table for estimating MO2C in METs during bicycle ergometer tests.
• To develop and validate a more accurate formula for METs estimation in subjects undergoing exercise myocardial perfusion SPECT.

Main Methods:

• MO2C in METs was measured via gas-exchange analysis in 97 healthy subjects (Group I).
• Estimated METs using a standard table (watts, weight) were compared to measured values.
• A refined formula incorporating clinical and ergometric variables was validated in 289 subjects (Group II) with normal exercise myocardial perfusion SPECT.

Main Results:

• A strong correlation (CCI: 0.93) was found between table-estimated and measured METs in Group I.
• The validated formula (METS=11.820-0.054×age-0.189×BMI+1.031×gender+0.020×watts) improved METs estimation in Group II.
• This formula reclassified 46.9% of Group II subjects compared to the standard table estimation.

Conclusions:

• The conventional table provides a reliable estimation of METs for bicycle exercise tests.
• For subjects with normal exercise myocardial perfusion SPECT, incorporating age and gender alongside watts and BMI significantly enhances METs estimation accuracy.