HEART RATE VARIABILITY AT REST AND DURING AN ORTHOSTATIC CHALLENGE AT DIFFERENT RANGES OF MxDMn VALUES IN FEMALE SKIERS IN THE TRAINING PROCESS

2020 ◽  
Vol 8 (1) ◽  
pp. 83-96
Author(s):  
Natalia Shlyk

The aim of the study is to analyze the heart rate variability (HRV) and to identify ranges of variability of cardiac intervals (MxDMn) at rest and during an orthostatic challenge, which result in the violation of cardioregulatory systems and decrease in the functional state of female skiers in the training process. Research methods and organization. We conducted dynamic HRV studies of 35 female skiers, including 12 young women aged 15-17 years in different periods of the training process. The analysis and physiological interpretation of HRV indicators were carried out in accordance with the recommendations of a group of Russian experts, the European Cardiology Society and the North American Society of Electrical Stimulation and Electrophysiology [1996, 2011], as well as Russian researchers [1,3,5,6]. We carried out 351 HRV studies at rest (5 minutes) and during an orthostatic challenge (6 minutes) using the "VARICARD 2.51" device and the "VARICARD MP" program in the morning before another training session. Using the "VARICARD MP" program allowed us to simultaneously register cardio intervals in four athletes. Results of the research. We paid particular attention to the variation range of cardiac intervals (MxDMn) during the individual analysis of HRV indicators in female skiers. The functional state of cardioregulatory systems at rest and during an orthostatic challenge was evaluated for different ranges of MxDMn values: <150 ms, 151-250 ms, 251-350 ms, 351-450 ms, 451-550 ms, 551-650 ms, and >650 ms. The paper contains tables with different numbers of optimal and adverse response to an orthostatic challenge in adult and young female skiers with different MxDMn values. At the same time, we paid particular attention to young female skiers who had equal training regime in the analysis of MxDMn values. The paper demonstrates the individual dynamics of MxDMn indicators at rest and during an orthostatic challenge in young female skiers during different periods of the training process. The research revealed that the smallest and largest MxDMn values cause the deregulation process at rest and the deterioration of vegetative reactivity during orthostatic testing. We revealed MxDMn values of female skiers in the range from <100 ms to >600 ms after the same training day before another training session. It indicates different activation of the sinus node control mechanisms and the body recovery processes. The paper contains the outcomes of dynamic HRV studies in different female skiers who had minimal or maximum MxDMn values at rest and adverse response to an orthostatic challenge during different periods of the training process. We demonstrated the outcomes of MxDMn values in an overtrained female skier during the transition of heart rate control mechanisms from a pronounced predominance of the autonomous regulation circuit in the preparatory period to a pronounced predominance of the central regulation circuit in the competition period. The paper contains the figures of cardiointervalograms, HRV and ECG scatergrams at rest and during an orthostatic challenge at different values of the variational range of cardiointervals (MxDMn). Conclusion. The research revealed an important role of identification of the ranges of variability of cardiac intervals (MxDMn) in the individual HRV analysis in the training process of female skiers for a more accurate assessment of the cardioregulatory system status and the sinus node functioning. The predominant type of vegetative regulation and orthostatic sampling play a great role in determination of the origin of MxDMn indicators at rest. We identified the ranges of MxDMn values at rest and during an orthostatic challenge in young female skiers, which result in deregulatory manifestations, vegetative reactivity and recovery processes disorders leading to overtraining. We identified the optimal values of the range of MxDMn values for young female skiers, which are common for the moderate prevalence of the autonomous regulation circuit.

2020 ◽  
Vol 8 (4) ◽  
pp. 46-66
Author(s):  
Natalia Shlyk ◽  
Alexander Alabuzhev

The aim of the study is to develop the standards of HRV indexes at rest and during an orthostatic challenge, taking into account different ranges of variability of cardiac intervals (MxDMn) of track and field athletes. The other purpose is to identify the features of changes in the standards in the training process in cases of malfunctions of cardioregulatory systems, sinus node functioning and recovery process, overtraining, and decrease in athletic performance. The authors used the results of individual dynamic express-tests of heart rate variability (HRV) in track and field athletes belonging to different specific training orientations to achieve the goals of the study. Research Methods and Organization. We carried out 1740 dynamic HRV measurements at rest and during an orthostatic challenge. The studies involved 56 track and field athletes (sprinters, middle distance runners and stayers) aged 18 to 29 years, belonging to the 1st adult category, Candidates Master of Sports and Masters of Sports, in different periods of the training process. We carried out HRV measurements in the laboratory of functional research methods of the Institute of physical culture and sports at Udmurt State University, as well as at training camps in the middle mountains (Kyrgyzstan, Kislovodsk) and on the plain (Elabuga). We examined the test subjects at rest in the morning after the previous training day, using the VARICARD 2.51 device and the ISCIM6 and VARICARD MP programs (Ryazan). We recorded cardio intervals of athletes for 5 minutes in lying position and for 6 minutes in standing position. We applied HRV measurements to one or four athletes simultaneously using the ISCIM6 and VARICARD MP programs. Research results. We assigned special emphasis to the assessment of changes in the variational range of cardiointervals (MxDMn) reflecting the state of cardiac regulation and the sinus node functioning during dynamic HRV studies in the training process of each runner. We identified seven MxDMn variation ranges from <150ms to >650ms. We revealed that each MxDMn variation range corresponds to a certain prevailing type of regulation. We demonstrated that frequent shifts of the MxDMn ranges from one level to another in the training process of runners indicate instability of cardiac regulation. We elaborated standards for the variational range of cardiointervals (MxDMn), taking into account the predominance of the HF and LF power in the HRV power spectrum for runners with different specific training orientations. We found that respiratory (HF) or vasomotor waves (LF) could prevail within the same MxDMn variation ranges, which points to a different autonomic balance. We revealed that at rest, the variational range of cardiointervals (MxDMn) depends more on the state of cardiac regulation and the sinus node functioning and less on the specifics of running. We often detected paradoxical reactions to an orthostatic challenge at low or extremely high MxDMn values in the overtrained runners. We determined that runners of any specific training orientation could increase their fitness, adaptive and reserve capabilities only in the context of the optimal regulation state, stable favorable ranges of MxDMn values, and the absence of paradoxical reactions to an orthostatic challenge. The paper contains tables with standard HRV indicators for different MxDMn variation ranges and consideration of the predominance of HF and LF waves at rest and during an orthostatic challenge, as well as examples of the results of HRV analysis at rest and during an orthostatic challenge in runners with different MxDMn variation ranges in the training process. Conclusion. The research demonstrated that the use of the HRV analysis method at rest and during an orthostatic challenge, taking into account the standards of MxDMn values in the training process of track and field athletes, is aimed at obtaining the necessary information about the stability of autonomic balance, autonomic reactivity and body reserves that ensure optimal adaptation and recovery processes.


2008 ◽  
Vol 1 (2) ◽  
pp. 187-199
Author(s):  
KATHRYN WALLS

According to the ‘Individual Psychology’ of Alfred Adler (1870–1937), Freud's contemporary and rival, everyone seeks superiority. But only those who can adapt their aspirations to meet the needs of others find fulfilment. Children who are rejected or pampered are so desperate for superiority that they fail to develop social feeling, and endanger themselves and society. This article argues that Mahy's realistic novels invite Adlerian interpretation. It examines the character of Hero, the elective mute who is the narrator-protagonist of The Other Side of Silence (1995) , in terms of her experience of rejection. The novel as a whole, it is suggested, stresses the destructiveness of the neurotically driven quest for superiority. Turning to Mahy's supernatural romances, the article considers novels that might seem to resist the Adlerian template. Focusing, in particular, on the young female protagonists of The Haunting (1982) and The Changeover (1984), it points to the ways in which their magical power is utilised for the sake of others. It concludes with the suggestion that the triumph of Mahy's protagonists lies not so much in their generally celebrated ‘empowerment’, as in their transcendence of the goal of superiority for its own sake.


2020 ◽  
pp. 81-85
Author(s):  
E. P. Popova ◽  
O. T. Bogova ◽  
S. N. Puzin ◽  
D. A. Sychyov ◽  
V. P. Fisenko

Spectral analysis of heart rate variability gives an idea of the role of the autonomic nervous system in the regulation of chronotropic heart function. This method can be used to evaluate the effectiveness of drug therapy. Drug therapy should be carried out taking into account the individual clinical form of atrial fibrillation. Information about the vegetative status of the patient will undoubtedly increase the effectiveness of treatment. In this study, spectral parameters were studied in patients with newly diagnosed atrial fibrillation. The effect of antiarrhythmic drug class III amiodarone on the spectral parameters of heart rate variability was studied.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yanwen Wang ◽  
Cali Anderson ◽  
Halina Dobrzynski ◽  
George Hart ◽  
Alicia D’Souza ◽  
...  

AbstractPhysiological systems vary in a day-night manner anticipating increased demand at a particular time. Heart is no exception. Cardiac output is primarily determined by heart rate and unsurprisingly this varies in a day-night manner and is higher during the day in the human (anticipating increased day-time demand). Although this is attributed to a day-night rhythm in post-translational ion channel regulation in the heart’s pacemaker, the sinus node, by the autonomic nervous system, we investigated whether there is a day-night rhythm in transcription. RNAseq revealed that ~ 44% of the sinus node transcriptome (7134 of 16,387 transcripts) has a significant day-night rhythm. The data revealed the oscillating components of an intrinsic circadian clock. Presumably this clock (or perhaps the master circadian clock in the suprachiasmatic nucleus) is responsible for the rhythm observed in the transcriptional machinery, which in turn is responsible for the rhythm observed in the transcriptome. For example, there is a rhythm in transcripts responsible for the two principal pacemaker mechanisms (membrane and Ca2+ clocks), transcripts responsible for receptors and signalling pathways known to control pacemaking, transcripts from genes identified by GWAS as determinants of resting heart rate, and transcripts from genes responsible for familial and acquired sick sinus syndrome.


Biomedicine ◽  
2021 ◽  
Vol 41 (2) ◽  
pp. 274-277
Author(s):  
Priya S.A. ◽  
R. Rajalakshmi

  Introduction and Aim: Mental stress may impact dramatically on dynamic autonomic control on heart. Many studies have demonstrated association of high body mass index (BMI) with greater risk for cardiovascular disease with disturbance in autonomic neuronal activity. Analysis of Heart rate variability (HRV)during acute mental stress assesses the autonomic status of the individual. Hence, we aimed to study the effect of acute mental stress on time domain measures in obese adults.   Materials and Methods:Sixty male volunteers of 30 each in study group (obese individuals) and control group (non-obese individuals) were recruited for the study. A basal recording of ECG in lead II was done on all the individuals. Then they underwent mental arithmetic stress task for 5 minutes during which again ECG was recorded. The change in time domain measures of HRV during rest and stress task was analyzed and compared between both the groups.   Results: Analysis of time domain measures of HRV revealed a statistically significant increase (p ? 0.001) in mean heart rate in both obese and non-obese individuals, while rMSSD(root mean square differences of successive RR interval) and SDNN (standard deviation of all NN intervals) showed a statistically significant (p? 0.001) decrease in obese individuals and non-obese individuals did not show any statistically significant change during the mental stress task.   Conclusion: In response to acute mental stress there was increased heart rate in both the groups. But the autonomic neuronal activity differed by way of sympathetic dominance in non-obese individuals and parasympathetic withdrawal in obese individuals.  


2021 ◽  
pp. 69-70
Author(s):  
Pakanati Sujana ◽  
Venkata Mahesh Gandhavalla ◽  
K. Prabhakara Rao

Introduction: COVID19 is caused by SARS-CoV-2 which is primarily transmitted through respiratory droplets and contact routes. WHO recommended the use of personal protective equipment (PPE) for prevention and N95 respirators are critical components of PPE. Breathing through N95 respirator will impart stress in the individual and that can be assessed by heart rate variability (HRV). HRV measures the variation in time between each heartbeat controlled by autonomic nervous system (ANS), which is a non invasive reliable index to identify the ANS imbalances. Aims And Objectives: This study is aimed at assessing the HRV of Interns working in COVID19 wards using N95 respirators. Methodology: This study included 100 interns in whom short term HRV was recorded using the standard protocol. Lead II of ECG was recorded using AD instruments (ADI) 8channel polygraph and HRV was analysed using Labchart 8pro software. The recordings were taken before and 1hour after wearing N95 respirator. Results: Overall HRV (SDRR) was found to decrease signicantly after wearing N95 respirator for 1hr (p=0.000). Similarly, indices representing the parasympathetic component ( RMSSD and HF ) were also found to decrease signicantly with the use of N95 respirator. Low frequency (LF) power and LF/HF ratio increased signicantly with N95 respirator use (p=0.000). Conclusion: We conclude that using N95 respirator increased sympathetic activity reecting decreased HRV in our subjects Hence we recommend that it is better to change the duty pattern for interns.


2000 ◽  
Vol 42 (4) ◽  
pp. 219-224 ◽  
Author(s):  
Argenis TORRES ◽  
Diego F. DÁVILA ◽  
Carlos F. GOTTBERG ◽  
Jose H. DONIS ◽  
Gabriela ARATA DE BELLABARBA ◽  
...  

We administered arecoline to rats, with experimentally induced chagasic myocarditis, in order to study the sinus node sensitivity to a muscarinic agonist. Sixteen month old rats were inoculated with 200,000 T. cruzi parasites ("Y" strain). Between days 18 and 21 (acute stage), 8 infected rats and 8 age-matched controls received intravenous arecoline as a bolus injection at the following doses: 5.0, 10.0, 20.0, 40.0, and 80.0 mug/kg. Heart rate was recorded before, during and after each dose of arecoline. The remaining 8 infected animals and 8 controls were subjected to the same experimental procedure during the subacute stage, i.e., days 60 to 70 after inoculation. The baseline heart rate, of the animals studied during the acute stage (349 ± 68 bpm, mean ± SD), was higher than that of the controls (250 ± 50 bpm, p < 0.005). The heart rate changes were expressed as percentage changes over baseline values. A dose-response curve was constructed for each group of animals. Log scales were used to plot the systematically doubled doses of arecoline and the induced-heart rate changes. The slope of the regression line for the acutely infected animals (r = - 0.99, b =1.78) was not different from that for the control animals (r = - 0.97, b = 1.61). The infected animals studied during the subacute stage (r = - 0.99, b = 1.81) were also not different from the age-matched controls (r = - 0.99, b = 1.26, NS). Consequently, our results show no pharmacological evidence of postjunctional hypersensitivity to the muscarinic agonist arecoline. Therefore, these results indirectly suggest that the postganglionic parasympathetic innervation, of the sinus node of rats with autopsy proved chagasic myocarditis, is not irreversibly damaged by Trypanosoma cruzi.


1998 ◽  
Vol 64 (2) ◽  
pp. 192-203 ◽  
Author(s):  
Isabelle Ragueneau ◽  
Christian Laveille ◽  
Roeline Jochemsen ◽  
Guillemette Resplandy ◽  
Christian Funck-Brentano ◽  
...  

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
R Fenici ◽  
M Picerni ◽  
D Brisinda

Abstract Background Quantitative assessment of individual body adaptability to physical training performed with the purposes of health maintenance is particularly necessary in the elderly age, to avoid the risk of overstrain induced by inappropriate exercises workload and physical stress. For that purpose, heart rate monitors and heart rate variability (HRV) analysis are nowadays commercially available. However, their reliability to guide individualized fitness training in elderly people needs to be tested, knowing that users might not have medical education. Objective To preliminary quantify autonomic nervous system (ANS) responses to graded physical effort and recovery in healthy elderly basing on the parasympathetic nervous system (PNSi), the sympathetic nervous system (SNSi) and the stress (STRi) indices, derived by short-term and time-varying HRV analysis. Methods ECG of a 75 healthy male subject was monitored, from April to November 2020, during three times/week training sessions with a professional bike–ergometer. Each session consisted of 10 minutes baseline rest, 5 minutes warm-up, 30 minutes work and 10 minutes recovery. According to age, the training workload was graded from low (65–75 watt/min), to moderate (75–85 watt/min), semi-intensive (85–95 watt/min) and intensive (95–110 watt/min). For this pilot study, ECG data of only 40 training sessions (10 sessions for each workload to evaluate reproducibility) were analyzed with Kubios Premium software (version 3.4.1), in the time (TD) and frequency (FD) domains, with nonlinear (NL) methods and with time-varying (TV) algorithms. Short-time HRV was calculated from 2-minutes intervals. The PNSi, SNSi and STRi induced by each workload were averaged and compared. Results Average values of PNSi, SNSi and STRi were significantly different (p&lt;0.05) among training sessions carried out with different workloads (Table 1A) and among measurements obtained at rest, at every 5 minutes step of each 30 minutes training session, and at 1 and 5 minutes of recovery (Table 1B). Interestingly, the correlation between SNSi and STRi was strictly linear (R= 0,98), whereas that between PNSi and STRi was better fitted by a cubic function (R=0,82 with cubic vs 0.68 with linear function), when evaluated either as a function of the sessions' workloads (Figure 1A), or of four time-intervals of each training session (Figure 1B). PNSi and SNSi were inversely correlated, with cross-point at about 15 minutes of training and 75 watt/min workload. Conclusions The calculation of PNSi, SNSi and STRi from HRV analysis is an efficient method for quick and simplified quantitative assessment of dynamic ASN adaptation to effort-induced stress from HRV analysis. If confirmed, the method may be useful for safer and even remote monitoring of training/rehabilitation in elderly. However, more detailed evaluation of spectral and NL parameters may be necessary to interpret more complex patterns of abnormal cases. FUNDunding Acknowledgement Type of funding sources: None. Table 1 Figure 1


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