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Kaufmann S, Gronwald T, Herold F, Hoos O. Heart Rate Variability-Derived Thresholds for Exercise Intensity Prescription in Endurance Sports: A Systematic Review of Interrelations and Agreement with Different Ventilatory and Blood Lactate Thresholds. SPORTS MEDICINE - OPEN 2023; 9:59. [PMID: 37462761 DOI: 10.1186/s40798-023-00607-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 07/03/2023] [Indexed: 07/21/2023]
Abstract
BACKGROUND Exercise intensities are prescribed using specific intensity zones (moderate, heavy, and severe) determined by a 'lower' and a 'higher' threshold. Typically, ventilatory (VT) or blood lactate thresholds (LT), and critical power/speed concepts (CP/CS) are used. Various heart rate variability-derived thresholds (HRVTs) using different HRV indices may constitute applicable alternatives, but a systematic review of the proximity of HRVTs to established threshold concepts is lacking. OBJECTIVE This systematic review aims to provide an overview of studies that determined HRVTs during endurance exercise in healthy adults in comparison with a reference VT and/or LT concept. METHODS A systematic literature search for studies determining HRVTs in healthy individuals during endurance exercise and comparing them with VTs or LTs was conducted in Scopus, PubMed and Web of Science (until January 2022). Studies claiming to describe similar physiological boundaries to delineate moderate from heavy (HRVTlow vs. VTlow and/or LTlow), and heavy from severe intensity zone (HRVThigh vs. VThigh and/or LThigh) were grouped and their results synthesized. RESULTS Twenty-seven included studies (461 participants) showed a mean difference in relative HR between HRVTlow and VTlow of - 0.6%bpm in weighted means and 0.02%bpm between HRVTlow and LTlow. Bias between HR at HRVTlow and VTlow was 1 bpm (limits of agreement (LoA): - 10.9 to 12.8 bpm) and 2.7 bpm (LoA: - 20.4 to 25.8 bpm) between HRVTlow and LTlow. Mean difference in HR between HRVThigh and VThigh was 0.3%bpm in weighted means and 2.9%bpm between HRVThigh and LThigh while bias between HR at HRVThigh and VThigh was - 4 bpm (LoA: - 17.9 to 9.9 bpm) and 2.5 bpm (LoA: - 12.1 to 17.1 bpm) between HRVThigh and LThigh. CONCLUSION HRVTlow seems to be a promising approach for the determination of a 'lower' threshold comparable to VTlow and potentially for HRVThigh compared to VThigh, although the latter needs further empirical evaluation. LoA for both intensity zone boundaries indicates bias of HRVTs on an individual level. Taken together, HRVTs can be a promising alternative for prescribing exercise intensity in healthy, male athletes undertaking endurance activities but due to the heterogeneity of study design, threshold concepts, standardization, and lack of female participants, further research is necessary to draw more robust and nuanced conclusions.
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Affiliation(s)
- Sebastian Kaufmann
- Center for Sports and Physical Education, Faculty of Human Sciences, Julius-Maximilians-University Wuerzburg, Am Hubland/Sports Center, 97074, Würzburg, Germany.
| | - Thomas Gronwald
- Institute of Interdisciplinary Exercise Science and Sports Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Fabian Herold
- Research Group Degenerative and Chronic Diseases, Movement, Faculty of Health Sciences Brandenburg, University of Potsdam, Potsdam, Germany
| | - Olaf Hoos
- Center for Sports and Physical Education, Faculty of Human Sciences, Julius-Maximilians-University Wuerzburg, Am Hubland/Sports Center, 97074, Würzburg, Germany
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Muñoz-Diosdado A, Solís-Montufar ÉE, Zamora-Justo JA. Visibility Graph Analysis of Heartbeat Time Series: Comparison of Young vs. Old, Healthy vs. Diseased, Rest vs. Exercise, and Sedentary vs. Active. ENTROPY (BASEL, SWITZERLAND) 2023; 25:e25040677. [PMID: 37190463 PMCID: PMC10137780 DOI: 10.3390/e25040677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/11/2023] [Accepted: 04/13/2023] [Indexed: 05/17/2023]
Abstract
Using the visibility graph algorithm (VGA), a complex network can be associated with a time series, such that the properties of the time series can be obtained by studying those of the network. Any value of the time series becomes a node of the network, and the number of other nodes that it is connected to can be quantified. The degree of connectivity of a node is positively correlated with its magnitude. The slope of the regression line is denoted by k-M, and, in this work, this parameter was calculated for the cardiac interbeat time series of different contrasting groups, namely: young vs. elderly; healthy subjects vs. patients with congestive heart failure (CHF); young subjects and adults at rest vs. exercising young subjects and adults; and, finally, sedentary young subjects and adults vs. active young subjects and adults. In addition, other network parameters, including the average degree and the average path length, of these time series networks were also analyzed. Significant differences were observed in the k-M parameter, average degree, and average path length for all analyzed groups. This methodology based on the analysis of the three mentioned parameters of complex networks has the advantage that such parameters are very easy to calculate, and it is useful to classify heartbeat time series of subjects with CHF vs. healthy subjects, and also for young vs. elderly subjects and sedentary vs. active subjects.
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Affiliation(s)
- Alejandro Muñoz-Diosdado
- Instituto Politécnico Nacional, Unidad Profesional Interdisciplinaria de Biotecnología, Mexico City 07340, Mexico
| | - Éric E Solís-Montufar
- Instituto Politécnico Nacional, Unidad Profesional Interdisciplinaria de Biotecnología, Mexico City 07340, Mexico
| | - José A Zamora-Justo
- Instituto Politécnico Nacional, Unidad Profesional Interdisciplinaria de Biotecnología, Mexico City 07340, Mexico
- Instituto Tecnológico de Santo Domingo (INTEC), Santo Domingo 10602, Dominican Republic
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Buekers J, Stas M, Aerts R, Bruffaerts N, Dujardin S, Van Nieuwenhuyse A, Van Orshoven J, Chevance G, Somers B, Aerts JM, Garcia-Aymerich J. Daily allergy burden and heart rate characteristics in adults with allergic rhinitis based on a wearable telemonitoring system. Clin Transl Allergy 2023; 13:e12242. [PMID: 37186425 PMCID: PMC10126716 DOI: 10.1002/clt2.12242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 03/07/2023] [Accepted: 04/03/2023] [Indexed: 05/17/2023] Open
Abstract
BACKGROUND Allergic rhinitis includes a certain degree of autonomic imbalance. However, no information is available on how daily changes in allergy burden affect autonomic imbalance. We aimed to estimate associations between daily allergy burden (allergy symptoms and mood) and daily heart rate characteristics (resting heart rate and sample entropy, both biomarkers of autonomic balance) of adults with allergic rhinitis, based on real-world measurements with a wearable telemonitoring system. METHODS Adults with a tree pollen allergy used a smartphone application to self-report daily allergy symptoms (score 0-44) and mood (score 0-4), and a Mio Alpha 2 wristwatch to collect heart rate characteristics during two pollen seasons of hazel, alder and birch in Belgium. Associations between daily allergy burden and heart rate characteristics were estimated using linear mixed effects distributed lag models with a random intercept for individuals and adjusted for potential confounders. RESULTS Analyses included 2497 participant-days of 72 participants. A one-point increase in allergy symptom score was associated with an increase in next-day resting heart rate of 0.08 (95% CI: 0.02-0.15) beats per minute. A one-point increase in mood score was associated with an increase in same-day sample entropy of 0.80 (95% CI: 0.34-1.26) × 10-2 . No associations were found between allergy symptoms and heart rate sample entropy, nor between mood and resting heart rate. CONCLUSION Daily repeated measurements with a wearable telemonitoring system revealed that the daily allergy burden of adults with allergic rhinitis has systemic effects beyond merely the respiratory system.
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Affiliation(s)
- Joren Buekers
- ISGlobal, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain
- Measure, Model & Manage Bioresponses (M3-BIORES), Department of Biosystems, KU Leuven, Leuven, Belgium
| | - Michiel Stas
- Measure, Model & Manage Bioresponses (M3-BIORES), Department of Biosystems, KU Leuven, Leuven, Belgium
- Division of Forest, Nature and Landscape, Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium
| | - Raf Aerts
- Risk and Health Impact Assessment, Sciensano (Belgian Institute of Health), Brussels, Belgium
- Division of Ecology, Evolution and Biodiversity Conservation, KU Leuven, Leuven, Belgium
- Centre for Environmental Sciences, University of Hasselt, Hasselt, Belgium
- KU Leuven Plant Institute, KU Leuven, Leuven, Belgium
| | - Nicolas Bruffaerts
- Mycology and Aerobiology, Sciensano (Belgian Institute of Health), Brussels, Belgium
| | - Sebastien Dujardin
- Department of Geography, University of Namur, Namur, Belgium
- Institute for Life, Earth and Environment (ILEE), University of Namur, Namur, Belgium
| | - An Van Nieuwenhuyse
- Centre of Environment and Health, Department of Public Health and Primary Care, KU Leuven, Leuven, Belgium
- Department of Health Protection, Laboratoire National de Santé (LNS), Dudelange, Luxembourg
| | - Jos Van Orshoven
- Division of Forest, Nature and Landscape, Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium
| | - Guillaume Chevance
- ISGlobal, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain
| | - Ben Somers
- Division of Forest, Nature and Landscape, Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium
- KU Leuven Plant Institute, KU Leuven, Leuven, Belgium
- KU Leuven Urban Studies Institute, KU Leuven, Leuven, Belgium
| | - Jean-Marie Aerts
- Measure, Model & Manage Bioresponses (M3-BIORES), Department of Biosystems, KU Leuven, Leuven, Belgium
| | - Judith Garcia-Aymerich
- ISGlobal, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain
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Riganello F, Vatrano M, Tonin P, Cerasa A, Cortese MD. Heart Rate Complexity and Autonomic Modulation Are Associated with Psychological Response Inhibition in Healthy Subjects. ENTROPY (BASEL, SWITZERLAND) 2023; 25:152. [PMID: 36673293 PMCID: PMC9857955 DOI: 10.3390/e25010152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/10/2023] [Accepted: 01/10/2023] [Indexed: 06/17/2023]
Abstract
BACKGROUND the ability to suppress/regulate impulsive reactions has been identified as common factor underlying the performance in all executive function tasks. We analyzed the HRV signals (power of high (HF) and low (LF) frequency, Sample Entropy (SampEn), and Complexity Index (CI)) during the execution of cognitive tests to assess flexibility, inhibition abilities, and rule learning. METHODS we enrolled thirty-six healthy subjects, recording five minutes of resting state and two tasks of increasing complexity based on 220 visual stimuli with 12 × 12 cm red and white squares on a black background. RESULTS at baseline, CI was negatively correlated with age, and LF was negatively correlated with SampEn. In Task 1, the CI and LF/HF were negatively correlated with errors. In Task 2, the reaction time positively correlated with the CI and the LF/HF ratio errors. Using a binary logistic regression model, age, CI, and LF/HF ratio classified performance groups with a sensitivity and specificity of 73 and 71%, respectively. CONCLUSIONS this study performed an important initial exploration in defining the complex relationship between CI, sympathovagal balance, and age in regulating impulsive reactions during cognitive tests. Our approach could be applied in assessing cognitive decline, providing additional information on the brain-heart interaction.
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Affiliation(s)
| | | | - Paolo Tonin
- S. Anna Institute, Via Siris 11, 88900 Crotone, Italy
| | - Antonio Cerasa
- S. Anna Institute, Via Siris 11, 88900 Crotone, Italy
- Institute for Biomedical Research and Innovation (IRIB), National Research Council of Italy (CNR), 98100 Messina, Italy
- Pharmacotechnology Documentation and Transfer Unit, Preclinical and Translational Pharmacology, Department of Pharmacy, Health Science and Nutrition, University of Calabria, 87036 Rende, Italy
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García-Ceberino JM, Fuentes-García JP, Villafaina S. Impact of Basketball Match on the Pre-Competitive Anxiety and HRV of Youth Female Players. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:7894. [PMID: 35805552 PMCID: PMC9265481 DOI: 10.3390/ijerph19137894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/22/2022] [Accepted: 06/25/2022] [Indexed: 02/01/2023]
Abstract
The present study aimed to investigate the impact of a basketball competition on the pre-competitive anxiety and Heart Rate Variability (HRV) of young female basketball players. A total of 12 female basketball players participated in this cross-sectional study. Girls had a mean age of 14 (1.41) years old and a mean experience of 4 (0.85) years practicing basketball. The pre-competitive anxiety and the HRV was assessed the week before and immediately before and after the match. Results showed a significant reduction (p-value < 0.05) of the several HRV variables after the match compared to baseline and pre-competition measures. However, differences between baseline and pre-competition were not found. Furthermore, a significant increase in somatic anxiety after the competition was reported. Taking into account HRV, somatic anxiety, and cognitive anxiety results, young female basketball players did not exhibit an increase in pre-competition anxiety. HRV measurements before competition can help coaches and physical trainers to identify female players with higher pre-competitive anxiety and propose intervention to manage it. Future studies should investigate the impact of coaches and parents on the pre-competitive anxiety of female and male basketball players.
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Affiliation(s)
- Juan M. García-Ceberino
- Faculty of Humanities and Social Sciences, University of Isabel I, 09003 Burgos, Spain;
- Optimization of Training and Sports Performance Research Group (GOERD), University of Extremadura, 10003 Cáceres, Spain
| | - Juan Pedro Fuentes-García
- Universidad de Extremadura, Facultad de Ciencias del Deporte, Av. de la Universidad S/N, 10003 Cáceres, Spain;
| | - Santos Villafaina
- Universidad de Extremadura, Facultad de Ciencias del Deporte, Av. de la Universidad S/N, 10003 Cáceres, Spain;
- Departamento de Desporto e Saúde, Escola de Saúde e Desenvolvimento Humano, Universidade de Évora, 7004-516 Évora, Portugal
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Wu G, Liu H, Wu S, Liu G, Liang C. Can Heart Rate Variability (HRV) Be Used as a Biomarker of Thermal Comfort for Mine Workers? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18147615. [PMID: 34300066 PMCID: PMC8306794 DOI: 10.3390/ijerph18147615] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 07/10/2021] [Accepted: 07/14/2021] [Indexed: 11/16/2022]
Abstract
This study aimed to determine whether heart rate variability (HRV) can express the thermal comfort of mine workers. Eight subjects ran on a treadmill (5.5 km/h) to simulate heavy labor in three kinds of mining environments (22 °C/90%, 26 °C/90%, 30 °C/90%), respectively. Based on the measured electrocardiogram (ECG) data, the HRV of the subjects was calculated. The results showed that the HRV indices changed obviously under different temperature environments. In the neutral and hot environment, except for the LF, TP and LF/HF, there were significant differences in each index. However, there was no significant difference between the cold and neutral environments. The R-R intervals, the very low-frequency power (VLF), pNN20 and SampEN had strong negative correlation with the thermal sensation of people from sitting to work (ρ < −0.700). These indices may be used as thermal comfort predictive biomarkers of mine workers.
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Affiliation(s)
- Guoshan Wu
- School of Resource & Environment and Safety Engineering, Hunan University of Science and Technology, Xiangtan 411201, China; (S.W.); (G.L.)
- School of Energy and Building Environment Engineering, Guilin University of Aerospace Technology, Guilin 541004, China
- Correspondence: (G.W.); (H.L.); Tel.: +86-731-58290280 (G.W.)
| | - Heqing Liu
- School of Resource & Environment and Safety Engineering, Hunan University of Science and Technology, Xiangtan 411201, China; (S.W.); (G.L.)
- Correspondence: (G.W.); (H.L.); Tel.: +86-731-58290280 (G.W.)
| | - Shixian Wu
- School of Resource & Environment and Safety Engineering, Hunan University of Science and Technology, Xiangtan 411201, China; (S.W.); (G.L.)
- School of Energy and Building Environment Engineering, Guilin University of Aerospace Technology, Guilin 541004, China
| | - Guanglei Liu
- School of Resource & Environment and Safety Engineering, Hunan University of Science and Technology, Xiangtan 411201, China; (S.W.); (G.L.)
| | - Caihang Liang
- School of Mechanical and Electrical Engineering, Guilin University of Electronic Technology, Guilin 541004, China;
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Villafaina S, Castro MA, Pereira T, Carvalho Santos A, Fuentes-García JP. Neurophysiological and autonomic responses of high and low level chess players during difficult and easy chess endgames - A quantitative EEG and HRV study. Physiol Behav 2021; 237:113454. [PMID: 33971186 DOI: 10.1016/j.physbeh.2021.113454] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 05/01/2021] [Accepted: 05/03/2021] [Indexed: 11/24/2022]
Abstract
The aim of the present study was to analyze the heart rate variability (HRV) and the electroencephalographic (EEG) power spectrum in low and high performance chess players during easy and difficult chess endgames. A total of 28 chess players participated in this cross-sectional study. Participants were divided into two groups according to their ELO level (rating system used by the international chess federation): 1) high level chess players (more than 1600 of ELO score); and 2) low level chess players (ELO less than 1599 of ELO score). Chess players had to complete two easy and two difficult endgames while the electroencephalographic activity and heart rate variability were assessed. High level chess players exhibit more alpha EEG power spectrums (p-value>0.05) during difficult than during easy chess endgames in the occipital area (O1 and O2 electrodes). Moreover, high performance players showed a reduced autonomic modulation (p-value>0.05) during the difficult chess endgames which low performance players did not reach. These results could suggest that high level chess players adapt their neurophysiological response to the task demand.
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Affiliation(s)
- Santos Villafaina
- Faculty of Sport Science, University of Extremadura, Avda: Universidad S/N, 10003, Cáceres, Spain.
| | - Maria António Castro
- Polytechnic Institute of Coimbra, Coimbra Health School, 3046-854 Coimbra, Portugal; University of Coimbra, Centre for Mechanical and Engineering Materials and Processes, 3030-788 Coimbra, Portugal.
| | - Telmo Pereira
- Polytechnic Institute of Coimbra, Coimbra Health School, 3046-854 Coimbra, Portugal.
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Mujib Kamal S, Babini MH, Krejcar O, Namazi H. Complexity-Based Decoding of the Coupling Among Heart Rate Variability (HRV) and Walking Path. Front Physiol 2020; 11:602027. [PMID: 33324242 PMCID: PMC7723866 DOI: 10.3389/fphys.2020.602027] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 10/14/2020] [Indexed: 01/04/2023] Open
Abstract
Walking is an everyday activity in our daily life. Because walking affects heart rate variability, in this research, for the first time, we analyzed the coupling among the alterations of the complexity of walking paths and heart rate. We benefited from the fractal theory and sample entropy to evaluate the influence of the complexity of paths on the complexity of heart rate variability (HRV) during walking. We calculated the fractal exponent and sample entropy of the R-R time series for nine participants who walked on four paths with various complexities. The findings showed a strong coupling among the alterations of fractal dimension (an indicator of complexity) of HRV and the walking paths. Besides, the result of the analysis of sample entropy also verified the obtained results from the fractal analysis. In further studies, we can analyze the coupling among the alterations of the complexities of other physiological signals and walking paths.
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Affiliation(s)
| | | | - Ondrej Krejcar
- Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Králové, Hradec Králové, Czechia
| | - Hamidreza Namazi
- School of Engineering, Monash University Malaysia, Selangor, Malaysia.,Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Králové, Hradec Králové, Czechia
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Solís-Montufar EE, Gálvez-Coyt G, Muñoz-Diosdado A. Entropy Analysis of RR-Time Series From Stress Tests. Front Physiol 2020; 11:981. [PMID: 32903750 PMCID: PMC7438833 DOI: 10.3389/fphys.2020.00981] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 07/20/2020] [Indexed: 11/14/2022] Open
Abstract
The RR-interval time series or tachograms obtained from electrocardiograms have been widely studied since they reflect the cardiac variability, and this is an indicative of the health status of a person. The tachogram can be seen as a highly non-linear and complex time series, and therefore, should be analyzed with non-linear techniques. In this work, several entropy measures, Sample Entropy (SampEn), Approximate Entropy (ApEn), and Fuzzy Entropy (FuzzyEn) are used as a measure of heart rate variability (HRV). Tachograms belonging to thirty-nine subjects were obtained from a cardiac stress test consisting of a rest period followed by a period of moderate physical activity. Subjects are grouped according to their physical activity using the IPAQ sedentary and active questionnaire, we work with youth and middle-aged adults. The entropy measures for each group show that for the sedentary subjects the values are high at rest and decrease appreciably with moderate physical activity, This happens for both young and middle-aged adults. These results are highly reproducible. In the case of the subjects that exercise regularly, an increase in entropy is observed or they tend to retain the entropy value that they had at rest. It seems that there is a possible correlation between the physical condition of a person with the increase or decrease in entropy during moderate physical activity with respect to the entropy at rest. It was also observed that entropy during longer physical activity tests tends to decrease as fatigue accumulates, but this decrease is small compared to the change that occurs when going from rest to physical activity.
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Affiliation(s)
- Eric E. Solís-Montufar
- Unidad Profesional Interdisciplinaria de Biotecnología, Instituto Politécnico Nacional, Mexico City, Mexico
- Centro de Investigación en Computación, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Gonzalo Gálvez-Coyt
- Unidad Profesional Interdisciplinaria de Biotecnología, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Alejandro Muñoz-Diosdado
- Unidad Profesional Interdisciplinaria de Biotecnología, Instituto Politécnico Nacional, Mexico City, Mexico
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Porta A, Valencia JF, Cairo B, Bari V, De Maria B, Gelpi F, Barbic F, Furlan R. Are Strategies Favoring Pattern Matching a Viable Way to Improve Complexity Estimation Based on Sample Entropy? ENTROPY 2020; 22:e22070724. [PMID: 33286495 PMCID: PMC7517267 DOI: 10.3390/e22070724] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 06/26/2020] [Accepted: 06/29/2020] [Indexed: 11/16/2022]
Abstract
It has been suggested that a viable strategy to improve complexity estimation based on the assessment of pattern similarity is to increase the pattern matching rate without enlarging the series length. We tested this hypothesis over short simulations of nonlinear deterministic and linear stochastic dynamics affected by various noise amounts. Several transformations featuring a different ability to increase the pattern matching rate were tested and compared to the usual strategy adopted in sample entropy (SampEn) computation. The approaches were applied to evaluate the complexity of short-term cardiac and vascular controls from the beat-to-beat variability of heart period (HP) and systolic arterial pressure (SAP) in 12 Parkinson disease patients and 12 age- and gender-matched healthy subjects at supine resting and during head-up tilt. Over simulations, the strategies estimated a larger complexity over nonlinear deterministic signals and a greater regularity over linear stochastic series or deterministic dynamics importantly contaminated by noise. Over short HP and SAP series the techniques did not produce any practical advantage, with an unvaried ability to discriminate groups and experimental conditions compared to the traditional SampEn. Procedures designed to artificially increase the number of matches are of no methodological and practical value when applied to assess complexity indexes.
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Affiliation(s)
- Alberto Porta
- Department of Biomedical Sciences for Health, University of Milan, 20133 Milan, Italy;
- Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato, San Donato Milanese, 20097 Milan, Italy; (V.B.); (F.G.)
- Correspondence: ; Tel.: +39-02-5277-4382
| | - José Fernando Valencia
- Department of Electronic Engineering, Universidad de San Buenaventura, Cali 760033, Colombia;
| | - Beatrice Cairo
- Department of Biomedical Sciences for Health, University of Milan, 20133 Milan, Italy;
| | - Vlasta Bari
- Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato, San Donato Milanese, 20097 Milan, Italy; (V.B.); (F.G.)
| | | | - Francesca Gelpi
- Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato, San Donato Milanese, 20097 Milan, Italy; (V.B.); (F.G.)
| | - Franca Barbic
- Department of Internal Medicine, IRCCS Humanitas Clinical and Research Center, Humanitas University, 20089 Rozzano, Italy; (F.B.); (R.F.)
| | - Raffaello Furlan
- Department of Internal Medicine, IRCCS Humanitas Clinical and Research Center, Humanitas University, 20089 Rozzano, Italy; (F.B.); (R.F.)
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Heart and Brain Responses to Real Versus Simulated Chess Games in Trained Chess Players: A Quantitative EEG and HRV Study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:ijerph16245021. [PMID: 31835514 PMCID: PMC6950455 DOI: 10.3390/ijerph16245021] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 12/05/2019] [Accepted: 12/06/2019] [Indexed: 11/17/2022]
Abstract
The aim of the present study was to investigate how the heart and the brain react to playing chess with a computer versus in a real context in chess players. We also aim to investigate if familiarization with simulated practice leads to changes in heart rate variability (HRV) and the electroencephalographic (EEG) power spectrum. We designed a cross-sectional study, enrolling 27 chess players. They were randomly assigned to 3 minutes plus 2-second chess games: one with a computer (simulated scenario), and another in a real context. Additionally, participants were divided into two groups according to their level of familiarization of playing chess in a computer context. While they were playing, HRV and EEG were continuously recorded. Differences in HRV and EEG theta power spectrum between playing chess in a real or a simulated scenario were not found in chess players (p-value > 0.05). When participants were divided into groups (familiarized and unfamiliarized with simulated chess practice), significant differences were observed in HRV and EEG (p-value < 0.05). The EEG theta power spectrum was significantly lower, and HRV was higher in unfamiliarized players during the simulated scenario, which could indicate that they were less focused in a simulated environment than in a real context. Therefore, familiarization with simulated environments should be taken into account during the training process to achieve the best performance.
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Tiwari A, Albuquerque I, Parent M, Gagnon JF, Lafond D, Tremblay S, H. Falk T. Multi-Scale Heart Beat Entropy Measures for Mental Workload Assessment of Ambulant Users. ENTROPY 2019; 21:e21080783. [PMID: 33267496 PMCID: PMC7515312 DOI: 10.3390/e21080783] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 08/07/2019] [Accepted: 08/08/2019] [Indexed: 12/02/2022]
Abstract
Mental workload assessment is crucial in many real life applications which require constant attention and where imbalance of mental workload resources may cause safety hazards. As such, mental workload and its relationship with heart rate variability (HRV) have been well studied in the literature. However, the majority of the developed models have assumed individuals are not ambulant, thus bypassing the issue of movement-related electrocardiography (ECG) artifacts and changing heart beat dynamics due to physical activity. In this work, multi-scale features for mental workload assessment of ambulatory users is explored. ECG data was sampled from users while they performed different types and levels of physical activity while performing the multi-attribute test battery (MATB-II) task at varying difficulty levels. Proposed features are shown to outperform benchmark ones and further exhibit complementarity when used in combination. Indeed, results show gains over the benchmark HRV measures of 24.41% in accuracy and of 27.97% in F1 score can be achieved even at high activity levels.
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Affiliation(s)
- Abhishek Tiwari
- Institut National de la Research Scientifique, Université du Québec, Montréal, QC H3A 0E7, Canada
- Correspondence:
| | - Isabela Albuquerque
- Institut National de la Research Scientifique, Université du Québec, Montréal, QC H3A 0E7, Canada
| | - Mark Parent
- Institut National de la Research Scientifique, Université du Québec, Montréal, QC H3A 0E7, Canada
| | | | - Daniel Lafond
- Thales Research and Technology, Québec, QC G1P 4P5, Canada
| | | | - Tiago H. Falk
- Institut National de la Research Scientifique, Université du Québec, Montréal, QC H3A 0E7, Canada
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13
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Nguyen Phuc Thu T, Hernández AI, Costet N, Patural H, Pichot V, Carrault G, Beuchée A. Improving methodology in heart rate variability analysis for the premature infants: Impact of the time length. PLoS One 2019; 14:e0220692. [PMID: 31398196 PMCID: PMC6688831 DOI: 10.1371/journal.pone.0220692] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 07/22/2019] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Heart rate variability (HRV) has been emerging in neonatal medicine. It may help for the early diagnosis of pathology and estimation of autonomous maturation. There is a lack of standardization and automation in the selection of the sequences to analyze and some features have not been explored in this specific population. The main objective of this study was to analyze the impact of the time length of the sequences on the estimation of linear and non-linear HRV features, including horizontal visibility graphs (HVG). METHODS HRV features were repeatedly measured with linear and non-linear methods on 2-, 5-, 10-minute sequences selected from the longest 15-min sequence and recorded on a weekly basis in 39 infants less than 31 weeks at birth. The associations between HRV measurements were analyzed through principal component analysis and k-means clustering. The effects of the time lengths on HRV measurements and post-menstrual age (PMA) were analyzed by linear mixed effect model for repeated measures. RESULTS The domains of analysis were concordant for their descriptive parameters of short (rMSSD, SD1 and HF) and long-term (SD, SD2 and LF) variability. α1 was correlated with the LF/HF and SD2/SD1. DC and AC were correlated with short-term variability estimates and significantly increased with GA and PMA. Shortening the windows of analysis increased the random measurement error for all the features and increased the bias for all but short term features and HVGs. CONCLUSION The linear and non-linear measurements of HRV are correlated each other. Shortening the windows of analysis increased the random error for all the features and increased the bias for all but short term features and HVGs. Short-term HRV can be an index for evaluating the maturation in whatever sequence length.
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Affiliation(s)
- Trang Nguyen Phuc Thu
- Laboratoire Traitement du Signal et de l’Image (LTSI – UMR 1099), Université de Rennes 1, Centre Hospitalier Universitaire de Rennes, Inserm, Rennes, France
- * E-mail:
| | - Alfredo I. Hernández
- Laboratoire Traitement du Signal et de l’Image (LTSI – UMR 1099), Université de Rennes 1, Centre Hospitalier Universitaire de Rennes, Inserm, Rennes, France
| | - Nathalie Costet
- Laboratoire Traitement du Signal et de l’Image (LTSI – UMR 1099), Université de Rennes 1, Centre Hospitalier Universitaire de Rennes, Inserm, Rennes, France
| | - Hugues Patural
- Pôle Mère-Enfants, Réanimation Néonatale – Hôpital Nord, Centre Hospitalier Universitaire Saint-Etienne, Saint-Etienne, France
- Système nerveux autonome - Epidémiologie Physiologie Ingénierie Santé (SNA-EPIS 4607), Université Jean Monnet, Saint-Etienne, France
| | - Vincent Pichot
- Système nerveux autonome - Epidémiologie Physiologie Ingénierie Santé (SNA-EPIS 4607), Université Jean Monnet, Saint-Etienne, France
| | - Guy Carrault
- Laboratoire Traitement du Signal et de l’Image (LTSI – UMR 1099), Université de Rennes 1, Centre Hospitalier Universitaire de Rennes, Inserm, Rennes, France
| | - Alain Beuchée
- Laboratoire Traitement du Signal et de l’Image (LTSI – UMR 1099), Université de Rennes 1, Centre Hospitalier Universitaire de Rennes, Inserm, Rennes, France
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14
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Fuentes-García JP, Villafaina S, Collado-Mateo D, de la Vega R, Olivares PR, Clemente-Suárez VJ. Differences Between High vs. Low Performance Chess Players in Heart Rate Variability During Chess Problems. Front Psychol 2019; 10:409. [PMID: 30863351 PMCID: PMC6400145 DOI: 10.3389/fpsyg.2019.00409] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Accepted: 02/11/2019] [Indexed: 11/26/2022] Open
Abstract
Background: Heart rate variability (HRV) has been considered as a measure of heart-brain interaction and autonomic modulation, and it is modified by cognitive and attentional tasks. In cognitive tasks, HRV was reduced in participants who achieved worse results. This could indicate the possibility of HRV predicting cognitive performance, but this association is still unclear in a high cognitive load sport such as chess. Objective: To analyze modifications on HRV and subjective perception of stress, difficulty and complexity in different chess problem tasks. Design: HRV was assessed at baseline. During the chess problems, HRV was also monitored, and immediately after chess problems the subjective stress, difficulty and complexity were also registered. Methods: A total of 16 male chess players, age: 35.19 (13.44) and ELO: 1927.69 (167.78) were analyzed while six chess problem solving tasks with different level of difficulty were conducted (two low level, two medium level and two high level chess problems). Participants were classified according to their results into two groups: high performance or low performance. Results: Friedman test showed a significant effect of tasks in HRV indexes and perceived difficulty, stress and complexity in both high and low performance groups. A decrease in HRV was observed in both groups when chess problems difficulty increased. In addition, HRV was significantly higher in the high performance group than in the low performance group during chess problems. Conclusion: An increase in autonomic modulation was observed to meet the cognitive demands of the problems, being higher while the difficulty of the tasks increased. Non-linear HRV indexes seem to be more reactive to tasks difficulty, being an interesting and useful tool in chess training.
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Affiliation(s)
| | | | - Daniel Collado-Mateo
- Faculty of Sport Science, University of Extremadura, Cáceres, Spain.,Facultad de Educación, Universidad Autónoma de Chile, Talca, Chile
| | - Ricardo de la Vega
- Department of Physical Education, Sport and Human Movement, Autonomous University of Madrid, Madrid, Spain
| | - Pedro R Olivares
- Facultad de Educación, Universidad Autónoma de Chile, Talca, Chile.,Faculty of Education, Psychology and Sport Sciences, University of Huelva, Huelva, Spain
| | - Vicente Javier Clemente-Suárez
- Faculty of Sports Sciences, Universidad Europea de Madrid, Madrid, Spain.,Grupo de Investigación Cultura, Educación y Sociedad, Universidad de la Costa, Barranquilla, Colombia
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15
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Kuang D, Cui L, Kuang S, Yang R, Chen X, Zhang L, Lv R, Ou S, Song C. Effect of gender-related depression on heart rate variability during an autonomic nervous test. Psychiatry Res 2019; 272:258-264. [PMID: 30594758 DOI: 10.1016/j.psychres.2018.12.099] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 12/18/2018] [Accepted: 12/18/2018] [Indexed: 11/15/2022]
Abstract
Patients with depression have lower heart rate variability (HRV) compared with controls. However, studies have indicated HRV difference between male and female controls. The gender effect might be interactive with the depression effect on the HRV, resulting in a low accuracy of recognising the patients with depression from the controls. Our study explores the effect of gender-related depression on HRV. Four ANS tests including resting, deep breathing, Valsalva, and orthostatic test are employed as stimuli. HRV were collected from 182 subjects comprising 91 depressive patients (33 females/58 males) and 91 controls (33 females/58 males) in the four tests. Time and frequency domains and nonlinear parameters are employed to quantify HRV. Two-way ANOVA is applied to evaluate the effect of gender-related depression. Most HRV parameters of the patients significantly differ from those of the controls, but some parameters indicate different depression effect between the males and females in the deep breathing and Valsalva test. Some HRV parameters illustrate significant difference between the male and female controls. Therefore, the effect of depression on HRV of each gender should be investigated.
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Affiliation(s)
- Danni Kuang
- Department of Biomedical Engineering, South China University of Technology, Guangzhou, China
| | - Liqian Cui
- The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Shiyuan Kuang
- The Affiliate Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), China
| | - Rongqian Yang
- Department of Biomedical Engineering, South China University of Technology, Guangzhou, China; Guangdong Engineering Technology Research Center for Translational Medicine of Mental Disorders, China; Department of Therapeutic Radiology, Yale University, New Haven, CT 06520, USA.
| | - Xiuwen Chen
- Medical Devices Research & Testing Center, South China University of Technology, Guangzhou, China
| | - Lei Zhang
- Shenzhen Sayes Medical Technology Co., Ltd., Shenzhen, China
| | - Ruixue Lv
- Shenzhen Sayes Medical Technology Co., Ltd., Shenzhen, China
| | - Shanxing Ou
- General Hospital of Guangzhou Military Command of PLA, Guangzhou, China
| | - Chuanxu Song
- Shenzhen Sayes Medical Technology Co., Ltd., Shenzhen, China
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16
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Validating team communication data using a transmission-duration threshold and voice activity detection algorithm. Behav Res Methods 2018; 51:384-397. [PMID: 30421180 DOI: 10.3758/s13428-018-1141-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The processes underlying team effectiveness can be understood by analyzing the temporal dynamics of team communication sequences. The results of such analyses have shown that the complexity of team communication is associated with team performance on task-related variables, and hence communication complexity statistics have been proposed for use as measures for real-time feedback on team performance. In two analyses of historical team communication sequences, we found that filtering via use of a transmission-duration threshold and voice activity detection algorithm resulted in significant changes in complexity relative to not filtering the data or using a transmission-duration filter alone. The use of these filtering techniques showed significant effects on the complexity of communication sequences in both a laboratory-based experiment, with participants with little experience with voice communication protocols, and in a mission simulation with trained military operators. There was also a significant non-linear relationship between the complexity of communication sequences and task performance. However, an analysis of the impact of the changes in communication dynamics gained through filtering did not demonstrate that the changed temporal dynamics of filtered data better explained team performance. It is concluded that pre-filtering of invalid communication data should be included during the data cleaning stage of statistical analysis as a matter of good scientific practice. Furthermore, such use of filtering will ensure that inferences made about the relationship between the complexity of communication between team members and their performance are not confounded by the presence of invalid communication events.
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17
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Singh V, Gupta A, Sohal JS, Singh A. A unified non-linear approach based on recurrence quantification analysis and approximate entropy: application to the classification of heart rate variability of age-stratified subjects. Med Biol Eng Comput 2018; 57:741-755. [PMID: 30390223 DOI: 10.1007/s11517-018-1914-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 10/09/2018] [Indexed: 11/26/2022]
Abstract
This paper presents a unified approach based on the recurrence quantification analysis (RQA) and approximate entropy (ApEn) for the classification of heart rate variability (HRV). In this paper, the optimum tolerance threshold (ropt) corresponding to ApEnmax has been used for RQA calculation. The experimental data length (N) of RR interval series (RRi) is optimized by taking ropt as key parameter. ropt is found to be lying within the recommended range of 0.1 to 0.25 times the standard deviation of the RRi, when N ≥ 300. Consequently, RQA is applied to the age stratified RRi and indices such as percentage recurrence (%REC), percentage laminarity (%LAM), and percentage determinism (%DET) are calculated along with ApEnmax, [Formula: see text], [Formula: see text], and an index namely the radius differential (RD). Certain standard HRV statistical indices such as mean RR, standard deviation of RR (or NN) interval (SDNN), and the square root of the mean squared differences of successive RR intervals (RMSSD) (Eur Hear J 17:354-381, 1996) are also found for comparison. It is observed that (i) RD can discriminate between the elderly and young subjects with a value of 0.1151 ± 0.0236 (mean ± SD) and 0.0533 ± 0.0133 (mean ± SD) respectively for the elderly and young subjects and is found to be statistically significant with p < 0.05. (ii) Similar significant discrimination was obtained using [Formula: see text] with a value of 0.1827 ± 0.0382 (mean ± SD) and 0.2248 ± 0.0320 (mean ± SD) (iii) other significant indices were found to be %REC, %DET, %LAM, SDNN, and RMSSD; however, ApEnmax was found to be insignificant with p > 0.05. The above features of RRi time series were tested for classification using support vector machine (SVM) and multilayer perceptron neural network (MLPNN). Higher classification accuracy was achieved using SVM with a maximum value of 99.71%. Graphical abstract.
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Affiliation(s)
- Vikramjit Singh
- Department of Electronics and Communication Engineering, I K G Punjab Technical University, Jalandhar, Punjab, India.
| | - Amit Gupta
- Department of Electronics and Communication Engineering, I K G Punjab Technical University, Jalandhar, Punjab, India
| | - J S Sohal
- Ludhiana College of Engineering and Technology, Ludhiana, Punjab, India
| | - Amritpal Singh
- Department of Electrical Engineering, I K G Punjab Technical University, Jalandhar, Punjab, India
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18
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Napoli NJ, Demas MW, Mendu S, Stephens CL, Kennedy KD, Harrivel AR, Bailey RE, Barnes LE. Uncertainty in heart rate complexity metrics caused by R-peak perturbations. Comput Biol Med 2018; 103:198-207. [PMID: 30384177 DOI: 10.1016/j.compbiomed.2018.10.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Revised: 09/28/2018] [Accepted: 10/08/2018] [Indexed: 11/17/2022]
Abstract
Heart rate complexity (HRC) is a proven metric for gaining insight into human stress and physiological deterioration. To calculate HRC, the detection of the exact instance of when the heart beats, the R-peak, is necessary. Electrocardiogram (ECG) signals can often be corrupted by environmental noise (e.g., from electromagnetic interference, movement artifacts), which can potentially alter the HRC measurement, producing erroneous inputs which feed into decision support models. Current literature has only investigated how HRC is affected by noise when R-peak detection errors occur (false positives and false negatives). However, the numerical methods used to calculate HRC are also sensitive to the specific location of the fiducial point of the R-peak. This raises many questions regarding how this fiducial point is altered by noise, the resulting impact on the measured HRC, and how we can account for noisy HRC measures as inputs into our decision models. This work uses Monte Carlo simulations to systematically add white and pink noise at different permutations of signal-to-noise ratios (SNRs), time segments, sampling rates, and HRC measurements to characterize the influence of noise on the HRC measure by altering the fiducial point of the R-peak. Using the generated information from these simulations provides improved decision processes for system design which address key concerns such as permutation entropy being a more precise, reliable, less biased, and more sensitive measurement for HRC than sample and approximate entropy.
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Affiliation(s)
- Nicholas J Napoli
- Dept. of Electrical and Computer Engineering, University Virginia, Charlottesville, Va, 22904, United States; National Institute of Aerospace, Hampton, Va, 23681, United States.
| | - Matthew W Demas
- Systems and Information Engineering, University of Virginia, Charlottesville, Va, 22904, United States.
| | - Sanjana Mendu
- Systems and Information Engineering, University of Virginia, Charlottesville, Va, 22904, United States.
| | - Chad L Stephens
- NASA Langley Research Center, Hampton, Va, 23681, United States.
| | - Kellie D Kennedy
- NASA Langley Research Center, Hampton, Va, 23681, United States.
| | | | - Randall E Bailey
- NASA Langley Research Center, Hampton, Va, 23681, United States.
| | - Laura E Barnes
- Systems and Information Engineering, University of Virginia, Charlottesville, Va, 22904, United States; Data Science Institute, University of Virginia, Charlottesville, VA, 22904, United States.
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19
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Giles DA, Draper N. Heart Rate Variability During Exercise: A Comparison of Artefact Correction Methods. J Strength Cond Res 2018; 32:726-735. [PMID: 29466273 DOI: 10.1519/jsc.0000000000001800] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Giles, DA and Draper, N. Heart rate variability during exercise: a comparison of artefact correction methods. J Strength Cond Res 32(3): 726-735, 2018-There is a need for standard practice in the collection and processing of RR interval data recorded using heart rate monitors (HRMs) in research. This article assessed the validity of RR intervals and heart rate variability (HRV) data obtained using an HRM during incremental exercise and artefact correction methods. Eighteen participants completed an active orthostatic test and incremental running V[Combining Dot Above]O2max test, while simultaneous recordings using a Polar V800 HRM and an electrocardiogram were made. Artefacts were corrected by deletion; degree zero, linear, cubic, and spline interpolation; and Kubios HRV software. Agreement was assessed using percentage bias, effect size (ES), intraclass correlation coefficients (ICC), and Bland-Altman limits of agreement (LoA). Artefacts increased relative to exercise intensity, to a peak of 4.46% during 80-100% V[Combining Dot Above]O2max. Correction of RR intervals was necessary with unacceptably increased bias, LoA, and ES and reduced ICC in all but resting recordings. All correction methods resulted in data with reduced percentage bias and ES for resting and <60% V[Combining Dot Above]O2max recordings. However, at >60% V[Combining Dot Above]O2max, even with correction, large amounts of variation were present in HRV measures of root mean square of the successive difference of intervals, low-to-high frequency ratio, Poincaré dispersion perpendicular to the axis (SD1), and sample entropy. Linear interpolation produced RR intervals with the lowest bias and ES. However, caution should be given to HRV parameters at high exercise intensities, as large amounts of variation were still present. Recommendations for minimizing artefacts are discussed, along with guidelines for their identification, correction, and reporting.
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Affiliation(s)
- David A Giles
- Department of Life Sciences, College of Life and Natural Sciences, University of Derby, Derby United Kingdom
| | - Nick Draper
- School of Health Sciences, University of Canterbury, Christchurch, New Zealand
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20
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Xia Y, Yang L, Zunino L, Shi H, Zhuang Y, Liu C. Application of Permutation Entropy and Permutation Min-Entropy in Multiple Emotional States Analysis of RRI Time Series. ENTROPY 2018; 20:e20030148. [PMID: 33265239 PMCID: PMC7512665 DOI: 10.3390/e20030148] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Revised: 02/14/2018] [Accepted: 02/15/2018] [Indexed: 11/18/2022]
Abstract
This study’s aim was to apply permutation entropy (PE) and permutation min-entropy (PME) over an RR interval time series to quantify the changes in cardiac activity among multiple emotional states. Electrocardiogram (ECG) signals were recorded under six emotional states (neutral, happiness, sadness, anger, fear, and disgust) in 60 healthy subjects at a rate of 1000 Hz. For each emotional state, ECGs were recorded for 5 min and the RR interval time series was extracted from these ECGs. The obtained results confirm that PE and PME increase significantly during the emotional states of happiness, sadness, anger, and disgust. Both symbolic quantifiers also increase but not in a significant way for the emotional state of fear. Moreover, it is found that PME is more sensitive than PE for discriminating non-neutral from neutral emotional states.
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Affiliation(s)
- Yirong Xia
- School of Control Science and Engineering, Shandong University, Jinan, 250061, China
| | - Licai Yang
- School of Control Science and Engineering, Shandong University, Jinan, 250061, China
- Correspondence: (L.Y.); (C.L.); Tel.: +86-135-83111153 (L.Y.); +86-159-52039150 (C.L.); Fax: +86-531-88392024 (L.Y.); +86-25-83793993 (C.L.)
| | - Luciano Zunino
- Centro de Investigaciones Ópticas (CONICET La Plata—CIC), C.C. 3, 1897 Gonnet, Argentina
- Departamento de Ciencias Básicas, Facultad de Ingeniería, Universidad Nacional de La Plata (UNLP), 1900 La Plata, Argentina
| | - Hongyu Shi
- School of Control Science and Engineering, Shandong University, Jinan, 250061, China
| | - Yuan Zhuang
- School of Control Science and Engineering, Shandong University, Jinan, 250061, China
| | - Chengyu Liu
- School of Instrument Science and Engineering, Southeast University, Nanjing 210018, China
- Correspondence: (L.Y.); (C.L.); Tel.: +86-135-83111153 (L.Y.); +86-159-52039150 (C.L.); Fax: +86-531-88392024 (L.Y.); +86-25-83793993 (C.L.)
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21
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Kuang D, Yang R, Chen X, Lao G, Wu F, Huang X, Lv R, Zhang L, Song C, Ou S. Depression recognition according to heart rate variability using Bayesian Networks. J Psychiatr Res 2017; 95:282-287. [PMID: 28926794 DOI: 10.1016/j.jpsychires.2017.09.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2017] [Revised: 08/20/2017] [Accepted: 09/08/2017] [Indexed: 11/18/2022]
Abstract
BACKGROUND Doctors mainly use scale tests and subjective judgment in the clinical diagnosis of depression. Researches have demonstrated that depression is associated with the dysfunction of the autonomic nervous system (ANS), where its modulation can be evaluated by heart rate variability (HRV). Depression patients have lower HRV than healthy subjects. Therefore, HRV may be used to distinguish depression patients from healthy people. METHODS HRV signals were collected from 76 female subjects composed of 38 depression patients and 38 healthy people. Time domain, frequency domain, and non-linear features were extracted from the HRV signals of these subjects, who were subjected to the Ewing test as an ANS stimulus. Then, these multiple features were input into Bayesian networks, served as a classifier, to distinguish depression patients from healthy people. Hence, accuracy, sensitivity, and specificity were calculated to evaluate the performance of the classifier. RESULTS Recognition results indicate 86.4% accuracy, 89.5% sensitivity, and 84.2% specificity. The individuals subjected to the Ewing test showed better recognition results than those at individual test states (resting state, deep breathing state, Valsalva state, and standing state) of the Ewing test. The root mean square of successive differences (RMSSD) of the HRV exhibits a significant relevance with recognition. CONCLUSION Bayesian networks can be applied to the recognition of depression patients from healthy people and the recognition results demonstrate the significant association between depression and HRV. The Ewing test is a good ANS stimulus for acquiring the difference of HRV between depression patients and healthy people to recognize depression. The RMSSD of the HRV is important in recognition and may be a significant index in distinguishing depression patients from healthy people.
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Affiliation(s)
- Danni Kuang
- Department of Biomedical Engineering, South China University of Technology, Guangzhou, China
| | - Rongqian Yang
- Department of Biomedical Engineering, South China University of Technology, Guangzhou, China.
| | - Xiuwen Chen
- Department of Biomedical Engineering, South China University of Technology, Guangzhou, China
| | - Guohui Lao
- The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Fengchun Wu
- The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Xiong Huang
- The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, China
| | - Ruixue Lv
- Shenzhen Sayes Medical Technology Co., Ltd., Shenzhen, China
| | - Lei Zhang
- Shenzhen Sayes Medical Technology Co., Ltd., Shenzhen, China
| | - Chuanxu Song
- Shenzhen Sayes Medical Technology Co., Ltd., Shenzhen, China
| | - Shanxing Ou
- General Hospital of Guangzhou Military Command of PLA, Guangzhou, China
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22
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Weippert M, Behrens M, Mau-Moeller A, Bruhn S, Behrens K. Cycling before and after Exhaustion Differently Affects Cardiac Autonomic Control during Heart Rate Matched Exercise. Front Physiol 2017; 8:844. [PMID: 29163192 PMCID: PMC5671980 DOI: 10.3389/fphys.2017.00844] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 10/10/2017] [Indexed: 11/17/2022] Open
Abstract
During cycling before (PRE) and after exhaustion (POST) different modes of autonomic cardiac control might occur due to different interoceptive input and altered influences from higher brain centers. We hypothesized that heart rate variability (HRV) is significantly affected by an interaction of the experimental period (PRE vs. POST) and exercise intensity (HIGH vs. LOW; HIGH = HR > HR at the lactate threshold (HRLT), LOW = HR ≤ HRLT) despite identical average HR. Methods: Fifty healthy volunteers completed an incremental cycling test until exhaustion. Workload started with 30 W at a constant pedaling rate (60 revolutions · min−1) and was gradually increased by 30 W · 5 min−1. Five adjacent 60 s inter-beat (R-R) interval segments from the immediate recovery period (POST 1–5 at 30 W and 60 rpm) were each matched with their HR-corresponding 60 s-segments during the cycle test (PRE 1–5). An analysis of covariance was carried out with one repeated-measures factor (PRE vs. POST exhaustion), one between-subject factor (HIGH vs. LOW intensity) and respiration rate as covariate to test for significant effects (p < 0.050) on the natural log-transformed root mean square of successive differences between adjacent R-R intervals (lnRMSSD60s). Results: LnRMSSD60s was significantly affected by the interaction of experimental period × intensity [F(1, 242) = 30.233, p < 0.001, ηp2 = 0.111]. LnRMSSD60s was higher during PRE compared to POST at LOW intensity (1.6 ± 0.6 vs. 1.4 ± 0.6 ms; p < 0.001). In contrast, at HIGH intensity lnRMSSD60s was lower during PRE compared to POST (1.0 ± 0.4 vs. 1.2 ± 0.4 ms; p < 0.001). Conclusion: Identical net HR during cycling can result from distinct autonomic modulation patterns. Results suggest a pronounced sympathetic-parasympathetic coactivation immediately after the cessation of peak workload compared to HR-matched cycling before exhaustion at HIGH intensity. On the opposite, at LOW intensity cycling, a stronger coactivational cardiac autonomic modulation pattern occurs during PRE-exhaustion if compared to POST-exhaustion cycling. The different autonomic modes during these phases might be the result of different afferent and/or central inputs to the cardiovascular control centers in the brainstem.
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Affiliation(s)
| | - Martin Behrens
- Institute of Sport Science, University of Rostock, Rostock, Germany
| | - Anett Mau-Moeller
- Institute of Sport Science, University of Rostock, Rostock, Germany.,Department of Orthopaedics, Rostock University Medical Center, Rostock, Germany
| | - Sven Bruhn
- Institute of Sport Science, University of Rostock, Rostock, Germany
| | - Kristin Behrens
- Institute of Sport Science, University of Rostock, Rostock, Germany
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Entropy Analysis of Short-Term Heartbeat Interval Time Series during Regular Walking. ENTROPY 2017. [DOI: 10.3390/e19100568] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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24
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Pereira T, Almeida PR, Cunha JPS, Aguiar A. Heart rate variability metrics for fine-grained stress level assessment. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2017; 148:71-80. [PMID: 28774440 DOI: 10.1016/j.cmpb.2017.06.018] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 03/27/2017] [Accepted: 06/23/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND AND OBJECTIVES In spite of the existence of a multitude of techniques that allow the estimation of stress from physiological indexes, its fine-grained assessment is still a challenge for biomedical engineering. The short-term assessment of stress condition overcomes the limits to stress characterization with long blocks of time and allows to evaluate the behaviour change in real-world settings and also the stress level dynamics. The aim of the present study was to evaluate time and frequency domain and nonlinear heart rate variability (HRV) metrics for stress level assessment using a short-time window. METHODS The electrocardiogram (ECG) signal from 14 volunteers was monitored using the Vital JacketTM while they performed the Trier Social Stress Test (TSST) which is a standardized stress-inducing protocol. Window lengths from 220 s to 50 s for HRV analysis were tested in order to evaluate which metrics could be used to monitor stress levels in an almost continuous way. RESULTS A sub-set of HRV metrics (AVNN, rMSSD, SDNN and pNN20) showed consistent differences between stress and non-stress phases, and showed to be reliable parameters for the assessment of stress levels in short-term analysis. CONCLUSIONS The AVNN metric, using 50 s of window length analysis, showed that it is the most reliable metric to recognize stress level across the four phases of TSST and allows a fine-grained analysis of stress effect as an index of psychological stress and provides an insight into the reaction of the autonomic nervous system to stress.
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Affiliation(s)
- Tânia Pereira
- Telecommunications Institute, University of Porto, Portugal.
| | | | - João P S Cunha
- INESC TEC and Faculty of Engineering, University of Porto, Portugal
| | - Ana Aguiar
- Telecommunications Institute, University of Porto, Portugal
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25
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Balasubramanian K, Nagaraj N. Aging and cardiovascular complexity: effect of the length of RR tachograms. PeerJ 2016; 4:e2755. [PMID: 27957395 PMCID: PMC5144723 DOI: 10.7717/peerj.2755] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 11/04/2016] [Indexed: 01/08/2023] Open
Abstract
As we age, our hearts undergo changes that result in a reduction in complexity of physiological interactions between different control mechanisms. This results in a potential risk of cardiovascular diseases which are the number one cause of death globally. Since cardiac signals are nonstationary and nonlinear in nature, complexity measures are better suited to handle such data. In this study, three complexity measures are used, namely Lempel-Ziv complexity (LZ), Sample Entropy (SampEn) and Effort-To-Compress (ETC). We determined the minimum length of RR tachogram required for characterizing complexity of healthy young and healthy old hearts. All the three measures indicated significantly lower complexity values for older subjects than younger ones. However, the minimum length of heart-beat interval data needed differs for the three measures, with LZ and ETC needing as low as 10 samples, whereas SampEn requires at least 80 samples. Our study indicates that complexity measures such as LZ and ETC are good candidates for the analysis of cardiovascular dynamics since they are able to work with very short RR tachograms.
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Affiliation(s)
- Karthi Balasubramanian
- Department of Electronics and Communication Engineering, Amrita School of Engineering, Coimbatore, Amrita Vishwa Vidyapeetham, Amrita University, India
| | - Nithin Nagaraj
- Consciousness Studies Programme, National Institute of Advanced Studies, Bengaluru, Karnataka, India
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26
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Holper L, Seifritz E, Scholkmann F. Short-term pulse rate variability is better characterized by functional near-infrared spectroscopy than by photoplethysmography. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:091308. [PMID: 27185106 DOI: 10.1117/1.jbo.21.9.091308] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 04/18/2016] [Indexed: 05/29/2023]
Abstract
Pulse rate variability (PRV) can be extracted from functional near-infrared spectroscopy (fNIRS) (PRV(NIRS)) and photoplethysmography (PPG) (PRV(PPG)) signals. The present study compared the accuracy of simultaneously acquired PRV(NIRS) and PRV(PPG), and evaluated their different characterizations of the sympathetic (SNS) and parasympathetic (PSNS) autonomous nervous system activity. Ten healthy subjects were recorded during resting-state (RS) and respiratory challenges in two temperature conditions, i.e., room temperature (23°C) and cold temperature (4°C). PRV(NIRS) was recorded based on fNIRS measurement on the head, whereas PRV(PPG) was determined based on PPG measured at the finger. Accuracy between PRV(NIRS) and PRV(PPG), as assessed by cross-covariance and cross-sample entropy, demonstrated a high degree of correlation (r > 0.9), which was significantly reduced by respiration and cold temperature. Characterization of SNS and PSNS using frequency-domain, time-domain, and nonlinear methods showed that PRV(NIRS) provided significantly better information on increasing PSNS activity in response to respiration and cold temperature than PRV(PPG). The findings show that PRV(NIRS) may outperform PRV(PPG) under conditions in which respiration and temperature changes are present, and may, therefore, be advantageous in research and clinical settings, especially if characterization of the autonomous nervous system is desired.
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Affiliation(s)
- Lisa Holper
- University of Zurich, Department of Psychiatry, Psychotherapy, and Psychosomatics, Hospital of Psychiatry, Lenggstrasse 31, 8032 Zurich, Switzerland
| | - Erich Seifritz
- University of Zurich, Department of Psychiatry, Psychotherapy, and Psychosomatics, Hospital of Psychiatry, Lenggstrasse 31, 8032 Zurich, Switzerland
| | - Felix Scholkmann
- University Hospital Zurich, University of Zurich, Biomedical Optics Research Laboratory, Department of Neonatology, Frauenklinikstrasse 10, 8091 Zurich, Switzerland
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27
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Marwaha P, Sunkaria RK. Complexity quantification of cardiac variability time series using improved sample entropy (I-SampEn). AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2016; 39:755-63. [DOI: 10.1007/s13246-016-0457-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 06/02/2016] [Indexed: 10/21/2022]
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28
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Giles D, Draper N, Neil W. Validity of the Polar V800 heart rate monitor to measure RR intervals at rest. Eur J Appl Physiol 2015; 116:563-71. [PMID: 26708360 PMCID: PMC4751190 DOI: 10.1007/s00421-015-3303-9] [Citation(s) in RCA: 197] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 11/18/2015] [Indexed: 12/28/2022]
Abstract
Purpose To assess the validity of RR intervals and short-term heart rate variability (HRV) data obtained from the Polar V800 heart rate monitor, in comparison to an electrocardiograph (ECG). Method Twenty participants completed an active orthostatic test using the V800 and ECG. An improved method for the identification and correction of RR intervals was employed prior to HRV analysis. Agreement of the data was assessed using intra-class correlation coefficients (ICC), Bland–Altman limits of agreement (LoA), and effect size (ES). Results A small number of errors were detected between ECG and Polar RR signal, with a combined error rate of 0.086 %. The RR intervals from ECG to V800 were significantly different, but with small ES for both supine corrected and standing corrected data (ES <0.001). The bias (LoA) were 0.06 (−4.33 to 4.45 ms) and 0.59 (−1.70 to 2.87 ms) for supine and standing intervals, respectively. The ICC was >0.999 for both supine and standing corrected intervals. When analysed with the same HRV software no significant differences were observed in any HRV parameters, for either supine or standing; the data displayed small bias and tight LoA, strong ICC (>0.99) and small ES (≤0.029). Conclusions The V800 improves over previous Polar models, with narrower LoA, stronger ICC and smaller ES for both the RR intervals and HRV parameters. The findings support the validity of the Polar V800 and its ability to produce RR interval recordings consistent with an ECG. In addition, HRV parameters derived from these recordings are also highly comparable.
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Affiliation(s)
- David Giles
- Department of Life Sciences, College of Life and Natural Sciences, University of Derby, Buxton, 1 Devonshire Road, Buxton, Derbyshire, SK17 6RY, UK
| | - Nick Draper
- Department of Life Sciences, College of Life and Natural Sciences, University of Derby, Buxton, 1 Devonshire Road, Buxton, Derbyshire, SK17 6RY, UK.
- School of Sport and Physical Education, University of Canterbury, Christchurch, New Zealand.
| | - William Neil
- Department of Life Sciences, College of Life and Natural Sciences, University of Derby, Buxton, 1 Devonshire Road, Buxton, Derbyshire, SK17 6RY, UK
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29
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Weippert M, Behrens K, Rieger A, Kumar M, Behrens M. Effects of breathing patterns and light exercise on linear and nonlinear heart rate variability. Appl Physiol Nutr Metab 2015; 40:762-8. [DOI: 10.1139/apnm-2014-0493] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Despite their use in cardiac risk stratification, the physiological meaning of nonlinear heart rate variability (HRV) measures is not well understood. The aim of this study was to elucidate effects of breathing frequency, tidal volume, and light exercise on nonlinear HRV and to determine associations with traditional HRV indices. R–R intervals, blood pressure, minute ventilation, breathing frequency, and respiratory gas concentrations were measured in 24 healthy male volunteers during 7 conditions: voluntary breathing at rest, and metronome guided breathing (0.1, 0.2 and 0.4 Hz) during rest, and cycling, respectively. The effect of physical load was significant for heart rate (HR; p < 0.001) and traditional HRV indices SDNN, RMSSD, lnLFP, and lnHFP (p < 0.01 for all). It approached significance for sample entropy (SampEn) and correlation dimension (D2) (p < 0.1 for both), while HRV detrended fluctuation analysis (DFA) measures DFAα1 and DFAα2 were not affected by load condition. Breathing did not affect HR but affected all traditional HRV measures. D2 was not affected by breathing; DFAα1 was moderately affected by breathing; and DFAα2, approximate entropy (ApEn), and SampEn were strongly affected by breathing. DFAα1 was strongly increased, whereas DFAα2, ApEn, and SampEn were decreased by slow breathing. No interaction effect of load and breathing pattern was evident. Correlations to traditional HRV indices were modest (r from –0.14 to –0.67, p < 0.05 to <0.01). In conclusion, while light exercise does not significantly affect short-time HRV nonlinear indices, respiratory activity has to be considered as a potential contributor at rest and during light dynamic exercise.
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Affiliation(s)
- Matthias Weippert
- Institute of Sport Science, University of Rostock, Rostock, Mecklenburg-Vorpommern, Germany
- Institute of Exercise Physiology and Public Health, Rostock, Mecklenburg-Vorpommern, Germany
| | - Kristin Behrens
- Institute of Exercise Physiology and Public Health, Rostock, Mecklenburg-Vorpommern, Germany
| | - Annika Rieger
- Institute of Exercise Physiology and Public Health, Rostock, Mecklenburg-Vorpommern, Germany
| | - Mohit Kumar
- University of Rostock, Rostock, Mecklenburg-Vorpommern, Germany
| | - Martin Behrens
- Institute of Sport Science, University of Rostock, Rostock, Mecklenburg-Vorpommern, Germany
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30
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Entropy Measures in the Assessment of Heart Rate Variability in Patients with Cardiodepressive Vasovagal Syncope. ENTROPY 2015. [DOI: 10.3390/e17031007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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