Search results for "Heart rate Variability"
showing 10 items of 232 documents
A validity and reliability study of Conditional Entropy Measures of Pulse Rate Variability
2019
In this work, we present the feasibility to use a simpler methodological approach for the assessment of the short-term complexity of Heart Rate Variability (HRV). Specifically, we propose to exploit Pulse Rate Variability (PRV) recorded through photoplethysmography in place of HRV measured from the ECG, and to compute complexity via a linear Gaussian approximation in place of the standard model-free methods (e.g., nearest neighbor entropy estimates) usually applied to HRV. Linear PRV-based and model-free HRV-based complexity measures were compared via statistical tests, correlation analysis and Bland-Altman plots, demonstrating an overall good agreement. These results support the applicabil…
Heart rate acceleration at relative workloads during treadmill and overground running for tracking exercise performance during functional overreaching
2020
AbstractMaximal rate of heart rate (HR) increase (rHRI) as a measure of HR acceleration during the transition from rest to exercise, or during an increase in workload, tracks exercise performance. rHRI assessed at relative rather than absolute workloads may track performance better, and a field test would increase applicability. This study therefore aimed to evaluate the sensitivity of rHRI assessed at individualised relative workloads during treadmill and overground running for tracking exercise performance. Treadmill running performance (5 km time trial; 5TTT) and rHRI were assessed in 11 male runners following 1 week of light training (LT), 2 weeks of heavy training (HT) and a 10-day tap…
Transthyretin familial amyloid polyneuropathy (TTR‐FAP): Parameters for early diagnosis
2017
Abstract Background Familial transthyretin amyloidosis is a life‐threatening disease presenting with sensorimotor and autonomic polyneuropathy. Delayed diagnosis has a detrimental effect on treatment and prognosis. To facilitate diagnosis, we analyzed data patterns of patients with transthyretin familial amyloid polyneuropathy (TTR‐FAP) and compared them to polyneuropathies of different etiology for clinical and electrophysiological discriminators. Methods Twenty‐four patients with TTR‐FAP and 48 patients with diabetic polyneuropathy (dPNP) were investigated (neurological impairment score NIS; neurological disability score NDS) in a cross‐sectional design. Both groups were matched for gende…
Sympathetic, metabolic adaptations, and oxidative stress in autism spectrum disorders: How far from physiology?
2018
Autism spectrum disorders (ASD) is a complex and multifaceted neurobehavioral syndrome with no specific cause still identified, despite the worldwide increasing (prevalence for 1,000 children from 6.7 to 14.6, between 2000 and 2012). Many biological and instrumental markers have been suggested as potential predictive factors for the precocious diagnosis during infancy and/or pediatric age. Many studies reported structural and functional abnormalities in the autonomic system in subjects with ASD. Sleep problems in ASD are a prominent feature, having an impact on the social interaction of the patient. Considering the role of orexins (A and B) in wake-sleep circadian rhythm, we could speculate…
Toward evidence-based severity assessment in rat models with repeated seizures: III. Electrical post-status epilepticus model
2019
Objective Ethical approval of experiments in chronic epilepsy models requires a careful balancing of the expected gain-in-knowledge with the level of distress. Thus recommendations for evidence-based severity assessment and classification are urgently needed for preclinical epilepsy research. Methods Therefore, we have completed a comprehensive analysis of alterations in behavioral, biochemical, and physiological parameters in a rat electrical post-status epilepticus model. Selected parameters were repeatedly analyzed during different experimental phases to obtain information about the level of distress throughout the course of the model. Results Behavioral patterns comprised an increase in…
Modulation of Heart Rate by Acute or Chronic Aerobic Exercise. Potential Effects on Blood Pressure Control.
2017
It was initially assumed that heart rate and arterial blood pressure were modulated by normal respiration and muscle contraction. The arterial baroreflex, an inverse relationship between blood pressure and heart rate, was later reported. Nonetheless, it was then assumed that those responses involved vagal modulation. We summarize available evidence on the modulation of heart rate by acute or chronic aerobic exercise as well as its potential implications on blood pressure (BP) control. Numerous studies have tried to clarify whether aerobic exercise modifies neurally-mediated vasoconstriction, but they report contradictory results. In view of these incongruities, the aim of this narrative rev…
Autonomic Modulation Improves in Response to Harder Performances While Playing Wind Instruments
2020
Background: Despite inducing autonomic benefits similar to exercise, playing wind instruments is a physical, and cognitive task of high attentional requirements, which demands musicians maximal efforts, leading to sympathetic hyperarousal and autonomic worsening. In this context of controversy, it remains unknown the autonomic response to playing highly demanding music performances, as compared to an easier one, which might be of interest in wind musicians' cardiovascular health. Objectives: This study aimed to investigate differences in the autonomic control of the heart with regard to task demands (TD), avoiding emotional influences (rehearsal performance). Methods: Eight healthy male pro…
Favouring emotional processing in improvisational music therapy through resonance frequency breathing: a single-case experimental study with a health…
2017
Resonance frequency breathing (RFB) is a form of slow breathing at around six breaths/min, whose immediate effects are to substantially increase heart rate variability (HRV) and to reduce stress levels. Since RFB has already been successfully used on its own to treat various emotional disorders, we wanted to evaluate its effect on emotional processing when used as a preparatory intervention in improvisational music therapy. To do so, we performed a single-subject experimental study with a healthy participant. We hypothesised that RFB would serve both as an emotional catalyst and emotional regulator, the actual outcome depending on the client’s current issues and needs. The study consisted o…
Redox and autonomic responses to acute exercise-post recovery following Opuntia ficus-indica juice intake in physically active women
2021
Background: The aim of this study was to investigate if the supplementation with Opuntia ficus-indica (OFI) juice may affect plasma redox balance and heart rate variability (HRV) parameters following a maximal effort test, in young physically active women. Methods: A randomized, double blind, placebo controlled and crossover study comprising eight women (23.25 ± 2.95 years, 54.13 ± 9.05 kg, 157.75 ± 0.66 cm and BMI of 21.69 ± 0.66 kg/m2) was carried out. A juice containing OFI diluted in water and a Placebo solution were supplied (170 ml; OFI = 50 ml of OFI juice + 120 ml of water; Placebo = 170 ml beverage without Vitamin C and indicaxanthin). Participants consumed the OFI juice or Placebo…
Nonlinear coupling is absent in acute myocardial patients but not healthy subjects.
2008
We investigated whether autonomic nervous system imbalance imposed by pharmacological blockades and associated with acute myocardial infarction (AMI) is manifested as modifications of the nonlinear interactions in heart rate variability signal using a statistically based bispectrum method. The statistically based bispectrum method is an ideal approach for identifying nonlinear couplings in a system and overcomes the previous limitation of determining in an ad hoc way the presence of such interactions. Using the improved bispectrum method, we found significant nonlinear interactions in healthy young subjects, which were abolished by the administration of atropine but were still present afte…