Predição do consumo máximo de oxigênio baseada nos parâmetros da variabilidade da frequência cardíaca durante o repouso em homens saudáveis

Abstract

This study aimed at determining a model for predicting the maximum oxygen consumption (VO2 max) based on HRV parameters. The experimental sample consists on data from 70 young male physically active adults. After recording the resting tachogram with a cardio-frequencymeter for 10 min, a maximal cardiopulmonary incremental test was performed to measure the VO2 max. According to VO2 max, subjects were firstly divided into two groups of 35, as high and low aerobic fitness. Logistic regression allowed to separate groups with 85.7% sensitivity, 88.5% specificity and 87.2% accuracy, using as independent variables the rate of successive RR interval changes larger than 50 mV (pNN50), and a novel cardiac deceleration rate (CDR), obtained as the average value of all incremental RR interval changes. A model for predicting VO2 max was them obtained by stepwise multiple linear regression assuming as independent variables the mean RR interval, pNN50 and CDR. The model, obtained by a 4-fold cross-validation, accounted for 76% of data variance, with a standard error of estimate 4.40 ml.kg-1 .min-1 . In conclusion, the obtained model showed an acceptable reliability, and might be tested as a tool for predicting the aerobic fitness in young healthy adult males in rest.