Effects of an isotonic beverage on autonomic regulation during and after exercise

Abstract

BackgroundWith prolonged physical activity, it is important to maintain adequate fluid balance. The impact of consuming isotonic drinks during and after exercise on the autonomic regulation of cardiac function is unclear. This study aimed to analyze the effects of consuming an isotonic drink on heart rate variability (HRV) during and after prolonged exercise.MethodsThirty-one young males (21.55 ± 1.89 yr) performed three different protocols (48 h interval between each stage): I) maximal exercise test to determine the load for the protocols; II) Control protocol (CP) and; III). Experimental protocol (EP). The protocols consisted of 10 min at rest with the subject in the supine position, 90 min of treadmill exercise (60% of VO2 peak) and 60 min of rest placed in the dorsal decubitus position. No rehydration beverage consumption was allowed during CP. During EP, however, the subjects were given an isotonic solution (Gatorade, Brazil) containing carbohydrate (30 g), sodium (225 mg), chloride (210 mg) and potassium (60 mg) per 500 ml of the drink. For analysis of HRV data, time and frequency domain indices were investigated. HRV was recorded at rest (5–10 min), during exercise (25–30 min, 55–60 min and 85–90 min) and post-exercise (5–10 min, 15–20 min, 25–30 min, 40–45 min and 55–60 min).ResultsRegardless of hydration, alterations in the SNS and PSNS were observed, revealing an increase in the former and a decrease in the latter. Hydrating with isotonic solution during recovery induced significant changes in cardiac autonomic modulation, promoting faster recovery of linear HRV indices.ConclusionHydration with isotonic solution did not significantly influence HRV during exercise; however, after exercise it promoted faster recovery of linear indices.

Cardiac autonomic regulation during exposure to auditory stimulation with classical baroque or heavy metal music of different intensities

“…Only series with more than 95% sinus rhythm were included in the study. [13,14] To analyze HRV in the frequency domain, low frequency (LF: 0.04 to 0.15 Hz) and high frequency (HF: 0.15 to 0.40 Hz) spectral components were used in ms 2 and normalized units. Normalizing data of the spectral analysis can be used to minimize the effects of changes in the very low frequency (VLF) band.…”

Influence of resistance training on cardiac autonomic modulation: literature review

“…7,8 This technique has been widely used to understand the phenomena involved in the autonomic nervous system in normal and pathological conditions. 9 While recognizing the importance of the autonomic nervous system to the organism, studies that describe the effects of resistance training on autonomic modulation are scarce when it comes to resistance training in a healthy young adult population.…”

Heart rate variability during hemodialysis in patients with chronic renal disease

“…On the other hand, it was suggested that during hemodialytic hypotension, autonomic changes are different, and are characterized by parasympathetic activation and sympathetic withdrawal and, as indicated by temporaryincreases in the power of HF component [6][7][8].The main objective of our study is to describe the behavior of HRV during hemodialysis. In order to clarify this mechanism we aimed to evaluate the acute effects of hemodialysis on cardiac autonomic regulation in patients with chronic renal disease.…”

“…The analysis in the time domain was performed by means of SDNN (standard deviation of normalto-normal RR intervals), the percentage of adjacent RR intervals with a difference of duration greater than 50ms (pNN50) and RMSSD (root-mean square of differences between adjacent normal RR intervals in a time interval) [8,9].…”

“…Only series with more than 95% sinus rhythm was included in the study. For calculation of the indices we used the HRV Analysis software (Kubios HRV v.1.1 for Windows, Biomedical Signal Analysis Group, Department of Applied Physics, University of Kuopio, Finland) [8].…”