Limiar de variabilidade da frequência cardíaca em teste progressivo de caminhada em diabéticos tipo 2

Abstract

Objective: The objective of this study was to analyze the cardiac autonomic nervous system modulation during exercise in subjects with type 2 diabetes. Methods: The nine man with 56,4 ± 5,6 years had been evaluated. The heart rate (HR) and heart rate variability (HRV) were measured in rest in the supine position. A walked gradual test was submitted for identification of the of HRV threshold (HRVT). The HR and R-R intervals were recorded by the use of Polar® equipment, S810i model. The R-R intervals were calculated by means of the Polar® Precision Performance software. Results: The HRVT, based on the criteria of Lima & Kiss (1999) - 5,4 ± 1,6 km.h-1 e 108 ± 16 beats·min-1- and Tulppo et al. (1998) - 5,2 ± 1,0 km.h-1 e 103 ± 7 beats·min-1, was identified in all the subjects. However, based on the linear regression criteria, it was not possible to be identified in 4 subjects (5,1 ± 1,1 km.h-1 e 104 ± 14 beats·min-1). There was no difference between the different criteria used to determine the HRVT. It was verified significant associations between the HRV of rest and intensity in the HRVT (r=0,75), using the criteria of Lima & Kiss (1999) and the HR of rest with the decreased percentage of the HR in the 5° minute of recovery (r=-0,69. Conclusion: Before the exposed, the obtaining of association evidences was verified between HRVT and the aerobic fitness, justifying the possible applicability of this threshold in the adaptation of the training loads for the walk in type 2.diabetics.