HEART RATE VARIABILITY AND BODY COMPOSITION AS VO_2MAX DETERMINANTS

VARIABILIDADE DA FREQUÊNCIA CARDÍACA E COMPOSIÇÃO CORPORAL COMO DETERMINANTES DO VO2MÁX

VARIABILIDAD DE LA FRECUENCIA CARDIACA Y COMPOSICIÓN CORPORAL COMO DETERMINANTES DEL VO2MAX

ABSTRACT

Introduction:

The maximum oxygen consumption (VO_2max) is the gold standard in the cardiorespiratory endurance assessment.

Objective:

This study aimed to develop a mathematical model that contains variables to determine the VO_2max of sedentary people.

Methods:

Twenty participants (10 men and 10 women) with a mean age of 19.8±1.77 years were included. For each participant, body composition (percentage of fat and muscle), heart rate variability (HRV) at rest (supine and standing), and VO_2max were evaluated through an indirect test on a cycloergometer. A multivariate linear regression model was developed from the data obtained, and the model assumptions were verified.

Results:

Using the data obtained, including percentage of fat (F), percentage of muscle (M), percentage of power at very low frequency (VLF), α-value of the detrended fluctuation analysis (DFAα1), heart rate (HR) in the resting standing position, and age of the participants, a model was established for men, which was expressed as VO_2max = 4.216 + (Age*0.153) + (F*0.110) - (M*0.053) - (VLF*0.649) - (DFAα1*2.441) - (HR*0.014), with R² = 0.965 and standard error = 0.146 L/min. For women, the model was expressed as VO_2max = 1.947 - (Age*0.047) + (F*0.024) + (M*0.054) + (VLF*1.949) - (DFAα1*0.424) - (HR*0.019), with R² = 0.987 and standard error = 0.077 L/min.

Conclusion:

The obtained model demonstrated the influence exerted by body composition, the autonomic nervous system, and age in the prediction of VO_2max.

Keywords:
body composition; autonomic nervous system; oxygen consumption; linear models