Absence of parasympathetic reactivation after maximal exercise

作者：de Oliveira Tiago Pecanha^*; Mattos Raphael de Alvarenga; Ferreira da Silva Rhenan Bartels; Rezende Rafael Andrade; Perrout de Lima Jorge Roberto

来源：Clinical Physiology and Functional Imaging, 2013, 33(2): 143-149.

DOI：10.1111/cpf.12009

• autonomic nervous system
• heart rate
• heart rate variability
• maximal exercise
• postexercise recovery

The ability of the human organism to recover its autonomic balance soon after physical exercise cessation has an important impact on the individual's health status. Although the dynamics of heart rate recovery after maximal exercise has been studied, little is known about heart rate variability after this type of exercise. The aim of this study is to analyse the dynamics of heart rate and heart rate variability recovery after maximal exercise in healthy young men. Fifteen healthy male subjects (21 center dot 7 +/- 3 center dot 4years; 24 center dot 0 +/- 2 center dot 1kgm2) participated in the study. The experimental protocol consisted of an incremental maximal exercise test on a cycle ergometer, until maximal voluntary exhaustion. After the test, recovery R-R intervals were recorded for 5min. From the absolute differences between peak heart rate values and the heart rate values at 1 and 5min of the recovery, the heart rate recovery was calculated. Postexercise heart rate variability was analysed from calculations of the SDNN and RMSSD indexes, in 30-s windows (SDNN30s and RMSSD30s) throughout recovery. One and 5min after maximal exercise cessation, the heart rate recovered 34 center dot 7 (+/- 6 center dot 6) and 75 center dot 5 (+/- 6 center dot 1) bpm, respectively. With regard to HRV recovery, while the SDNN30s index had a slight increase, RMSSD30s index remained totally suppressed throughout the recovery, suggesting an absence of vagal modulation reactivation and, possibly, a discrete sympathetic withdrawal. Therefore, it is possible that the main mechanism associated with the fall of HR after maximal exercise is sympathetic withdrawal or a vagal tone restoration without vagal modulation recovery.

• 出版日期2013-3