Vecchiato M; University of Padova, Padova, ITALY.
Aghi A; Nerini R; Borasio N; Gasperetti A; Quinto G; Battista
F; Bettini S; DI Vincenzo A; Ermolao A; Busetto L; Neunhaeuserer D

Medicine & Science in Sports & Exercise. 56(9):1732-1739, 2024 Sep 01.

PURPOSE: Cardiorespiratory fitness (CRF) is a critical marker of overall
health and a key predictor of morbidity and mortality, but the existing
prediction equations for CRF are primarily derived from general
populations and may not be suitable for patients with obesity.
METHODS: Predicted CRF from different non-exercise prediction equations
was compared with measured CRF of patients with obesity who underwent
maximal cardiopulmonary exercise testing (CPET). Multiple linear
regression was used to develop a population-specific nonexercise CRF
prediction model for treadmill exercise including age, sex, weight,
height, and physical activity level as determinants.
RESULTS: Six hundred sixty patients underwent CPET during the study
period. Within the entire cohort, R2 values had a range of 0.24 to 0.46.
Predicted CRF was statistically different from measured CRF for 19 of the
21 included equations. Only 50% of patients were correctly classified into
the measured CRF categories according to predicted CRF. A multiple model
for CRF prediction (mL.min -1 ) was generated ( R2 = 0.78) and validated
using two cross-validation methods.
CONCLUSIONS: Most used equations provide inaccurate estimates of CRF in
patients with obesity, particularly in cases of severe obesity and low
CRF. Therefore, a new prediction equation was developed and validated
specifically for patients with obesity, offering a more precise tool for
clinical CPET interpretation and risk stratification in this population.