Controlled Breathing Research Articles

THE RELATIONSHIP OF MOTHER'S EDUCATION, JOB, AGE AND EDUCATION TO BABY MASSAGE

Baby massage is a relaxation technique performed on babies and toddlers that has many benefits. Infant massage is great to help increase the baby's immune system, help relaxation, make it easier to sleep and help control fussiness and breathing. This study was conducted with the aim of knowing the relationship between mother's education, occupation, age and knowledge of infant massage. This study used quantitative research methods with a cross sectional research design. The study population consisted of 85 mothers and babies aged 1-12 months. The sampling method used the overall sampling method. The variables studied were presented in the form of frequency distribution tables, and tested using variance analysis and multiplication using a questionnaire tool. This research was conducted by TPMB Ririn Sevda Korini, SKM, S.Keb Tanjung Agung in July 2023. Data analysis was performed using Chi-square, univariate and bivariate statistical tests. Based on the results of univariate analysis, 40 (47.1%) respondents were well informed, out of 85 respondents who practiced baby massage, 56 (65%) respondents were well informed, 50 (58.8%) respondents were working, 48 (56.5%) respondents were old, and 40 (47%) respondents were highly educated. The results of bivariate analysis showed that there was a relationship between cognition and infant massage (p-value 0.023), between maternal employment and infant massage (p-value 0.033), age of mother and child massaged (p-value 0.02)3, value (p 0.041). There is a relationship between mother's education and infant massage (p-value 0.007).

A Systematic Review of Breathing Exercise Interventions: An Integrative Complementary Approach for Anxiety and Stress in Adult Populations.

Aim: Nurses are well-qualified to deliver integrative complementary therapy interventions, a holistic approach to assist individuals experiencing anxiety and stress. Self-regulated, controlled breathing exercises (a clinical approach) are reported to decrease anxiety and increase stress tolerance. The aim of this systematic review was to evaluate the effectiveness of breathing exercise interventions on the psychological and physiologic outcomes of anxiety and stress among adults and assess the state of the science in the post-COVID-19 population. Methods: A systematic review was conducted, and four scientific databases were searched: PubMed, CINAHL, EMBASE, and Web of Science. Inclusion criteria included: (1) peer-reviewed studies, (2) adults over 18, (3) breathing exercise interventions, and (4) anxiety or stress as outcomes. Results: Out of 309 studies identified, 19 were included. Twelve reported significant improvements in anxiety and nine reported significant improvements in stress following varying breathing exercise interventions (p < .05). No adverse events were reported. Conclusions: Breathing exercises were found to be effective in reducing anxiety and stress in adults, however, there continues to be limited evidence that includes large randomized controlled trials. Breathing exercises are a holistic care approach that can be safely implemented by nurses to decrease symptomatology among adults, including the post-COVID population.

Goggle-free swimming as autonomous water competence from the perspective of breath control on execution of a given distance

This study aimed to examine the ability of adolescents to maintain breathing rhythm while swimming with and without goggles, in the context of pedagogical interventions for implementation of water competence skills, rather than simply teaching swimming technique (strokes). 25 females and 25 males, 12–13 years old, swam the front crawl both with goggles and without goggles. Distance covered and the ability to maintain breathing rhythm were evaluated by experts. For both girls and boys, the lack of goggles reduced the breath control. The boys in contrast to the girls, could "swim" (cover a distance) but did not have the “competence” to swim effectively/safely—with breathing rhythm—regardless of the goggle factor. Goggle-free swimming as an autonomous component of water competence is highly recommended in elementary swimming education. The following elements for pedagogical intervention in the area of water competence development are proposed: (1) the formatting of breath control on the basis of the student's preferred, simplest form of swimming (not strokes); (2) the a priori treatment of swimming goggles as an unnecessary teaching aid; (3) the gender differences in area of both adaptation in visual perception (the goggles factor) and motor control (breath control factor) should be considered.

Autonomic and cognitive control in memory: Investigating the psychophysiological link using heart rate variability biofeedback.

Vagally mediated heart rate variability (vmHRV) at resting state has been associated to cognitive functions dependent on cognitive control, such as memory. However, little is known about the phasic interaction between cognitive and autonomic control. In a pre-registered within-between-subject designed experiment, the potential of vmHRV biofeedback to simultaneously stimulate vmHRV during memory processing and cognitive control over long-term memory was tested, along with investigating psychophysiological association. 71 young healthy adults completed (twice) a false memory task in virtual reality. Immediately before memory encoding and retrieval, participants practiced either vmHRV biofeedback or a control breathing exercise. Cognitive control over long-term memory was assessed as the confidence toward false memories and the capability to discriminate them from true memories. Resting-state vmHRV before each test and phasic vmHRV during memory encoding and retrieval were measured as the root mean square differences (RMSSD) in the heart period. vmHRV biofeedback had neither an immediate effect on measures of cognitive control over long-term memory nor on phasic RMSSD. Moreover, neither resting-state nor phasic vmHRV correlated to the cognitive scores. Consequently, the utility of HRV biofeedback as a psychophysiological stimulation tool and a link between vmHRV and cognitive control over long-term memory could not be verified. Exploratory analyses revealed that baseline shift in parasympathetic activity confounded the psychophysiological association. Future directions are provided that could shed light on the relationship between cognition and vmHRV.

Buoyancy control and air breathing in royal knifefish (Chitala blanci) and a new hypothesis for the early evolution of vertebrate air-breathing behaviors.

We present the first description of inspiration-first air breaths in royal knifefish, Chitala blanci, a ray-finned fish known to use four-stroke air breaths. Four-stroke breaths are used by nearly all ray-finned fish species that use their gas bladder to breathe air and are the ancestral breath type of ray-finned fishes. Interestingly, one such species, Amia calva, is known to perform two distinct breath types. Amia use four-stroke breaths when they need more oxygen and performs inspiration-first breaths to restore buoyancy. We observed that C. blanci also performs inspiration-first breaths and tested whether the two breath types are performed for the same functions in C. blanci as they are in Amia. We recorded the frequency of each breath type when exposed to aquatic hypoxia and two conditions of oxygen availability. We found that C. blanci performed more four-stroke breaths (81% ± 15% of total breaths) than inspiration-first breaths when exposed to aerial normoxia but performed more inspiration-first breaths (72% ± 40%) than four-stroke breaths when exposed to aerial hyperoxia. These patterns match those described for Amia and indicate that C. blanci performs four-stroke breaths in response to oxygen depletion and performs inspiration-first breaths to maintain buoyancy. Few studies have examined the role of air-breathing in buoyancy regulation. Decreasing buoyancy, rather than oxygen availability, to stimulate air breaths may reveal that inspiration-first breaths are more common among fishes than we are aware. We consider this possibility and present a new hypothesis for the origin and early evolution of air breathing in vertebrates.

Can scent-detection dogs detect the stress associated with trauma cue exposure in people with trauma histories? A proof-of-concept study.

Post-traumatic stress disorder (PTSD) is an impairing mental health condition with high prevalence among military and general populations alike. PTSD service dogs are a complementary and alternative intervention needing scientific validation. We investigated whether dogs can detect putative stress-related volatile organic compounds (VOCs) in the breath of people with trauma histories (54% with PTSD) exposed to personalized trauma cues. Breath samples were collected from 26 humans over 40 experimental sessions during a calm (control breath sample) and stressed state induced by trauma cue exposure (target breath sample). Two scent detection canines were presented with the samples in a two alternative forced choice (2AFC) discrimination and yes/no detection task. The 2AFC task assessed the dogs' ability to discriminate between the two states within the breath samples of one individual. The detection task determined their ability to generalize the target odour across different individuals and different stressful events of one individual. Signal Detection Theory was applied to assess dogs' sensitivity, specificity, precision, and response bias. The dogs performed at ∼90% accuracy across all sample sets in the discrimination experiment, and at 74% and 81% accuracy, respectively, in the detection experiment. Further analysis of dog olfactory performance in relation to human donor self-reported emotional responses to trauma cue exposure suggested the dogs may have been detecting distinct endocrine stress markers. One dog's performance correlated with the human donors' self-reported fear responses and the other dog's performance correlated with the human donors' self-reported shame responses. Based on these correlations between dog performance and donor self-report measures, we speculate that the VOCs each dog was detecting likely originated from the sympathetico-adreno-medullary axis (SAM; adrenaline, noradrenaline) in the case of the first dog and the hypothalamo-pituitary-adrenal axis (HPA; glucocorticoids) in the case of the second dog. Our proof-of-concept study is the first to demonstrate that some dogs can detect putative VOCs emitted by people with trauma histories when experiencing distress theoretically associated with the intrusion and arousal/reactivity symptoms of PTSD. Results have potential to improve the effectiveness and training protocol of PTSD service dogs with a focus on enhancing their alert function.

Acute effects of slow, controlled breathing exercises on arterial pressure and autonomic cardiac modulation in hypertensive patients

The aim of the present study was to evaluate the influence of slow, controlled breathing exercises (SCBE) on arterial pressure and autonomic cardiac modulation in hypertensive patients. 29 hypertensive patients were evaluation in two data collections (period between 1 to 3 days). In each evaluation, data were collected after 10 min of spontaneous breathing (between 12 and 20 breaths per minute – bpm) and 10 min of SCBE (12 bpm, in the rhythm of standardized verbal stimulus). The arterial pressure was evaluated by a multi-parameter monitor and the autonomic cardiac modulation by the rate variability technique. The SCBE reduced systolic arterial pressure (1st evaluation: -4.8 mmHg and 2nd evaluation: -4.3 mmHg), decreased sympathetic activity by 18% and modified autonomic modulation by about 50%. SCBE reduced both systolic arterial pressure and sympathetic activity and can be used in control arterial pressure of hypertensive patients.

An analytical approach for on-site analysis of breath samples for Δ9-tetrahydrocannabinol (THC).

Increased acceptance of cannabis containing the psychoactive component, Δ9-tetrahydrocannabinol (THC), raises concerns about the potential for impaired drivers and increased highway accidents. In contrast to the "breathalyzer" test, which is generally accepted for determining the alcohol level in a driver, there is no currently accepted roadside test for THC in a motorist. There is a need for an easily collectible biological sample from a potentially impaired driver coupled with an accurate on-site test to measure the presence and quantity of THC in a driver. A novel breath collection device is described, which includes three separate sample collectors for collecting identical A, B, and C breath samples from a subject. A simple one-step ethanol extraction of the "A" breath collector sample can be analyzed by UHPLC/selected ion monitoring (SIM) liquid chromatography/mass spectrometry (LC/MS) to provide qualitative and quantitative determination of THC in breath sample in less than 4 min for samples collected up to 6 h after smoking a cannabis cigarette. SIM LC/MS bioanalyses employed d3-THC as the stable isotope internal standard fortified in negative control breath samples for quantitation including replicates of six calibrator standards and three quality control (QC) samples. Subsequent confirmation of the same breath sample in the B collectors was then confirmed by a reference lab by LC/MS/MS analysis. Fit-for-purpose bioanalytical validation consistent with pharmaceutical regulated bioanalyses produced pharmacokinetic (PK) curves for the two volunteer cannabis smokers. These results produced PK curves, which showed a rapid increase of THC in the breath of the subjects in the first hour followed by reduced THC levels in the later time points. A simpler single-point calibration curve procedure with calibrators and QC prepared in ethanol provided similar results. Limitations to this approach include the higher cost and operator skill sets for the instrumentation employed and the inability to actually determine driver impairment.

79 The Effects of Mobile Based Resonant Frequency Breathing on Cognitive Performance in Healthy Young Adults with Elevated Stress

Objective:Finding effective, innovative, and accessible methods of coping with and mitigating stress has been increasingly relevant in the midst of the COVID-19 pandemic. To do so, it is important to understand the impact of acute stress responses on cognition, behavior, and emotional functioning. The young adult population in particular has been known to show higher levels of stress. Studies have shown that deep breathing interventions are associated with improved affect, decreased stress levels, and improved cognitive functioning. The autonomic nervous system, particularly the functioning of the vagus nerve, has been thought to be a key mechanism in the effect of breathing on stress and mood. Most studies to date investigating the efficacy of breathing practices in stress reduction and mood improvement have lacked appropriate methodology, including adequate control groups, randomization, and cross-sectional designs. This single-blind, randomized, waitlist-controlled study investigated the feasibility of using a mobile application to train in resonance frequency breathing and its efficacy in reducing stress and improving cognitive functioning in a non-clinical sample of young adults with elevated stress.Participants and Methods:80 healthy young adults with elevated stress levels were recruited from the NY/NJ community and the Queens College undergraduate research subject pool. Inclusion criteria: ages 18-29, Perceived Stress Scale score &gt;13. Exclusion criteria: regular (at least 3 times per week) practice of any form of meditation, yoga, or breathing exercise; severe medical or psychiatric disorder; active suicidal ideation; drug or alcohol abuse within the past year; use of medication with a known negative impact on cognition or autonomic nervous system (ANS) arousal. Participants were randomized to a waitlist control group or breathing group. Participants in the breathing group were instructed to complete 10-minute breathing sessions using the free mobile application “The Breathing App” twice a day for five days per week for four weeks. Cognitive assessments were administered over the phone (pre and post-treatment) and self-report measures were completed online due to quarantine restrictions.Results:There were no significant main effects of group across any of the neuropsychological variables, including verbal memory, letter fluency, category fluency, cognitive flexibility, processing speed, basic attention span, and working memory. This indicated that breathing training did not significantly impact neuropsychological performance. Mediation analysis also demonstrated that breathing training did not indirectly lead to improvement in basic attention, processing speed, working memory, set-shifting, verbal fluency, category fluency, or cognitive flexibility, through its effects on stress reduction.Conclusions:These results do not support literature suggesting that breathing at resonance frequency is associated with improved cognitive functioning such as greater cognitive flexibility, improved decision-making, stronger response inhibition, faster processing speed, and increased working memory. Future study designs should consider implementing active control groups (e.g., mindfulness meditation) and differential dosages of the breathing treatment.

Assessing cardiorespiratory interactions via lagged joint symbolic dynamics during spontaneous and controlled breathing.

Introduction: Joint symbolic analysis (JSA) can be utilized to describe interactions between time series while accounting for time scales and nonlinear features. JSA is based on the computation of the rate of occurrence of joint patterns built after symbolization. Lagged JSA (LJSA) is obtained from the more classical JSA by introducing a delay/lead between patterns built over the two series and combined to form the joint scheme, thus monitoring coordinated patterns at different lags. Methods: In the present study, we applied LJSA for the assessment of cardiorespiratory coupling (CRC) from heart period (HP) variability and respiratory activity (R) in 19 healthy subjects (age: 27-35years; 8 males, 11 females) during spontaneous breathing (SB) and controlled breathing (CB). The R rate of CB was selected to be indistinguishable from that of SB, namely, 15 breaths·minute-1 (CB15), or slower than SB, namely, 10 breaths·minute-1 (CB10), but in both cases, very rapid interactions between heart rate and R were known to be present. The ability of the LJSA approach to follow variations of the coupling strength was tested over a unidirectionally or bidirectionally coupled stochastic process and using surrogate data to test the null hypothesis of uncoupling. Results: We found that: i) the analysis of surrogate data proved that HP and R were significantly coupled in any experimental condition, and coupling was not more likely to occur at a specific time lag; ii) CB10 reduced CRC strength at the fastest time scales while increasing that at intermediate time scales, thus leaving the overall CRC strength unvaried; iii) despite exhibiting similar R rates and respiratory sinus arrhythmia, SB and CB15 induced different cardiorespiratory interactions; iv) no dominant temporal scheme was observed with relevant contributions of HP patterns either leading or lagging R. Discussion: LJSA is a useful methodology to explore HP-R dynamic interactions while accounting for time shifts and scales.

Benefits of Yin Yoga and Plank Exercise on Weight Loss in Overweight Adolescents

Background: Overweight is a physical condition caused by excessive accumulation of fat in the body due to an imbalance between food intake consumed and energy expended during bodily activities. Low physical activity has the potential to lead to obesity, especially when it starts as a child. The activities of children and adolescents are currently more playing gadgets and watching TV so that they have the potential to cause obesity. Overweight is a serious problem in Indonesia. This is because obesity will increase the risk of cardiovascular disease such as enlarged blood vessels, heart failure, stroke, fatty liver and hardening of the liver. Complications that can occur in overweight are heart attack, type II diabetes, stroke, hypertension, sleep apnea and breathing problems. To overcome the problematic consequences of being overweight are yin yoga and plank exercises. Yin yoga is currently one of the exercises that can reduce levels of fat in the body (burn bad calories in the body), relax the mind, and control breathing. Meanwhile, plank exercise is used to increase muscle strength. Plank movements help strengthen the muscles of the arms, shoulders, abdomen, legs, can also increase stability, and can burn up to 12 kcal of calories per round (healthy). This activity was carried out by physiotherapy students at the Lubuk Pakam Medistra Health Institute in the 2023 program with the aim of introducing the benefits of Yin yoga and plank exercises in overcoming and preventing the incidence of overweight among Physiotherapy students at the Lubuk Pakam Medistra Health Institute in 2023.

Influence of controlled breath on healthy adult autonomic heart modulation

Heart rate variability (HRV) is a technique that indirectly assesses the activities of the autonomic nervous system in the heart. However, during data collection there are controversies regarding the use of spontaneous or controlled breath. The aim of this research was to compare the effects of controlled and spontaneous breath on HRV in healthy adults.The present cross-sectional study held a sample of 52 healthy volunteers (22 male, 42.3%), average of 25 (±4) years old and body mass index 22.4 (±2.7) kgm-². All the volunteers were evaluated in 2 days (at most three days between the evaluations). On each day the data were collected with spontaneous and then controlled breath (12 breaths per minute - bpm: Inspiration/Expiration: 2/3). Data were collected with a pulse frequency meter (Polar brand, model 810i). The HRV was evaluated for time and frequency domain and was analyzed using an area corresponding to 5 minutes (containing at least 256 beats per minute) by Kubios program version 2.1. In the time domain, no differences were observed between spontaneous and controlled breath. In the frequency domain, the controlled breathing reduced sympathetic activity (p&lt;0.001) in approximately 14% and increased (p&lt;0.001) parasympathetic activity proportionally. The autonomic modulation evaluated by low frequency/ high frequency(LF/HF) ratio decreased (p&lt;0.001) in average -0.6 on the days evaluated. The controlled breathing (12 bpm) decrease sympathetic activity and increases parasympathetic by modifying the heart autonomic modulation.

Ventilatory Pattern Influences Tolerance to Normobaric Hypoxia in Healthy Adults

Tolerance to breathing in conditions with a decreased oxygen ratio is subject-specific. A normobaric hypoxia tolerance test (NHTT) is performed to assess the ability of each individual, as this may be influenced by genetic or personal factors such as age or gender. The aim of this study is to test the influence of deep breathing on hypoxia tolerance time. A total of 45 subjects (21 parachutists and 24 students) performed two NHTTs at 5050 m altitude (iAltitude). Arterial (SatO2) and muscle (SmO2) oxygen saturation were monitored with the Humon Hex® device. The first NHTT was performed with free breathing, without any instructions; and the second NHTT was performed with wide, slow, diaphragmatic breathing. The NHTT was terminated at the end of 10 min or when a value of less than 83% was obtained. The first NHTT was completed by 38.1% of parachutist and 33.3% of students while the second NHTT was completed by 85.7% and 75%, respectively. In the second NHTT, both parachutists and students had a significantly (p = 0.001) longer duration compared to the first NHTT. SmO2 and SatO2 values also increased significantly (p < 0.001) in both groups (p < 0.05). Performing controlled diaphragmatic breathing is successful in increasing hypoxia tolerance time and/or SatO2 values.

Effect of the forward head syndrome in the development of temporomandibular disorders

Bad habits, such as poor posture during the use of technological devices, poor abdominal control and oral breathing pattern can lead to a forward head position, which has important implications for the entire future of the individual, especially at the stomatognathic system. There is a strong association between temporomandibular disorders and forward head syndrome. Where the muscular component is the main affected, with the appearance of more trigger points at the level of the sternocleidomastoid muscles, upper trapezius, rectus capitis posterior and upper oblique capitis. Degenerative changes in the temporomandibular joint have been observed, but evidence is still lacking to ensure that Forward Head Syndrome is the etiological factor.

Adaptive Support Ventilation – A way different from traditional ventilation

Adaptive support ventilation (ASV) is a dual control mode of ventilation, which uses a closed loop control technique. This mode delivers controlled, time triggered and time cycled breaths when a patient is not breathing. If the patient has spontaneous breaths, it delivers flow cycled breaths and allows the patient to trigger and breathe spontaneously, either in between the controlled breaths or fully spontaneously. This mode is pressure limited for control, assist control and spontaneous breath. The pressure will vary depending on the target tidal volume and uses autoflow throughout the cycle. IntelliVent(R) is a closed loop mode of ventilation, an advance over the ASV mode where the ventilator automatically adjusts settings and optimises ventilation depending on the target settings and physiological information from the patient.

ДИАГНОСТИКА СИНДРОМА ВЕГЕТАТИВНОЙ ДИСФУНКЦИИ У ЮНЫХ СПОРТСМЕНОВ

Purpose: A review of the most common and effective from the point of view of evidence-based medicine methods for diagnosing autonomic dysfunction syndrome in young athletes. Material and methods: The data of domestic and foreign literature on the diagnosis of autonomic dysfunction syndrome were analyzed. The search was carried out using electronic databases MEDLINE, Embase, Scopus, Web of Science, eLIBRARY and Google Academy for the period from 2017 to 2022. For the search, we used keywords and their combinations: “vegetative dysfunction syndrome”, “athletes”, “diagnostics”, “functional tests”. A total of 28 sources analyzed Results: The autonomic dysfunction syndrome (ADS) is characterized by a significant polymorphism of clinical manifestations and is characterized by functional disorders of the activity of the cardiovascular, endocrine and other systems of the body. Diagnosis of this condition is associated with great difficulties associated with the nonspecificity of symptoms, their bright emotional color and the absence of morphological changes in organs. The frequent manifestation of ADS in childhood and adolescence, the proven relationship of symptoms with exercise and mental stress, determines the importance of early and effective diagnosis of this syndrome in young athletes. The key research methods for suspected autonomic dysfunction syndrome include taking anamnesis using special questionnaires and scales and conducting functional tests with registration of the parameters of the cardiovascular system (heart rate, blood pressure, HRV). The most common and informative functional tests: deep controlled breathing test, orthostatic test (active and passive), Valsalva test. Promising methods for diagnosing ADS include accelerometric tremorography and the study of baroreflex sensitivity. Also, for a deeper examination of a young athlete, it is recommended to use laboratory diagnostic methods to identify violations of the endocrine system, detect changes in lipid and carbohydrate metabolism, etc. Conclusions: At the moment, further research is needed to study the autonomic dysfunction syndrome and methods for its diagnosis.

Device-guided slow breathing alters postprandial oxidative stress in young adult males: A randomized sham-controlled crossover trial

Background and aimsSlow, deep breathing (SDB) lowers blood pressure (BP) though the underlying mechanisms are unknown. Redox improvements could facilitate hemodynamic adjustments with SDB though this has not been investigated. The purpose of this randomized, sham-controlled trial was to examine the acute effects of SDB on oxidative stress and endothelial function during a physiological perturbation (high-fat meal) known to induce oxidative stress. Methods and resultsSeventeen males (ages 18–35 years) were enrolled, and anthropometric measurements and 7-day physical activity monitoring were completed. Testing sessions consisted of 24-h diet recalls (ASA24), blood sample collection for superoxide dismutase (SOD) and thiobarbituric acid reactive substances (TBARS) analysis, and flow-mediated dilation (FMD). High-fat meals were ingested and 2-min breathing exercises (SDB or sham control breathing) were completed every 15 min during the 4-h postprandial phase. Blood sample collection and FMD were repeated 1-, 2-, and 4-h post meal consumption. Mean body mass index and step counts were 25.6 ± 4.3 kg/m2 and 8165 ± 4405 steps per day, respectively. Systolic and diastolic BP and nutrient intake 24 h prior were similar between conditions. No time or time by condition interaction effects were observed for FMD. The total area under the curve (AUC) for SOD was significantly lower during SDB compared to the sham breathing condition (p < 0.01). No differences were observed in TBARS AUC (p = 0.538). ConclusionsFindings from the current investigation suggest that SDB alters postprandial redox in the absence of changes in endothelial function in young, healthy males. Clinical trial registration number: NCT04864184. Clinical trials identifierNCT04864184.

The Effect of Meditation on Heart Rate Variability

Heart rate variability (HRV) has been utilized in both medicine and sports sciences as an important marker for managing stress, indicating diseased states, and monitoring training/recovery. HRV reflects the autonomic balance of the sympathetic (SNS) and parasympathetic (PNS) nervous systems. High PNS activity is correlated to high HRV. The frequency and time domains of an ECG may be analyzed to determine the influence of PNS activity. HRV has been shown to be influenced by exercise training; however, meditation and guiding breathing techniques may also influence HRV.PURPOSETo evaluate the effect of a short, guided meditation session on the measures of heart rate variability of inexperienced meditators.METHODS39 participants (18‐21 years) volunteered and gave informed consent. During the experimental session, a Polar H10 heart rate monitor was fitted around the subject to record a 15‐minute ECG. The breathing protocol consisted of sitting in a comfortable position and continuous 5‐minute stages of spontaneous breathing (SP1), controlled breathing (CB), and returning to spontaneous breathing (SP2). During CB, a 6 breath/min guided protocol was followed using a commercially available App. A one‐way ANOVA with repeated measures was conducted for each variable using SPSS, p &gt; 0.05.RESULTSCB produced a significant increase in heart rate from 70.6+11.9 bpm to 72.9+10.4 bpm (p&lt;0.005) during CB, and then decreased to 71.7+10.3 bpm (p&lt;0.05). Measures of the frequency domain included high frequency (HF) and low frequency (LF) power. HF significantly decreased from 49.2+21.1 nu during SP1, to 16.6+9.9 nu (p&lt;0.005), and returned to 34.6+18.3 nu (p&lt;0.005). For LF, SP1 was 50.9+21.0 nu, significancy increased to 83.4+9.9 nu (p&lt;0.005), and returned to 65.4+18.3 nu (p&lt;0.005). The measures of the time domain included rMSSD and SDNN. rMSSD at SP1 was 60.9+33.8, significantly increased to 74.2+36.6 (p&lt;0.005), and returned to 56.0+33.1 (p&lt;0.005). The SP1 for SDNN was 62.7+31.4, significantly increased to 110.4+39.6 (p&lt;0.005), and returned to 66.1+29.7 (p&lt;0.005). CONCLUSION: The direction and magnitude of change in frequency domain (HR, HF and LF) may initially suggest a dampening of the PNS. However, CB has been shown to initiate SNS activity which is represented in the frequency measures. In short‐term HRV measures, rMSSD and SDNN are the more appropriate measures to consider for the PNS activity. Thus, the results of this study indicate that a short session of CB may stimulate a PNS response.

Evaluation of Loaded Breathing on Inspiratory Intercostal Muscle Activation During High Frequency Spinal Cord Stimulation to Restore Breathing in Spinal Cord Injury – Animal Model

BackgroundHigh Frequency Spinal Cord Stimulation (HF‐SCS) is a unique method of inspiratory muscle activation and has the potential to restore breathing in ventilator dependent tetraplegic subjects. However, these subjects are 3‐4 times more likely to have sleep disordered breathing (SDB) and have a higher incidence of obstructive airways disease than individuals in the general population, resulting in an increased inspiratory load.ObjectiveTo examine the effects of increased inspiratory load (airway occlusion) on inspiratory intercostal muscle activation during HF‐SCS.MethodsIn 3 spinalized (C2 level) anesthetized dogs, recording electrodes were positioned in the parasternal (PA) and external (EI) intercostal muscles (2nd and 3rd interspaces respectively) to record multiunit (integrated) and single motor units (SMU) EMG activities. During HF‐SCS at functional residual capacity (FRC), respiratory muscle activity was assessed before and after single and multi‐breath airway occlusion.ResultsDuring HF‐SCS, tracheal occlusion resulted in augmentation of peak multi‐unit integrated EI, but little change in PA EMG activity. During the occluded breath, EI activity increased to 148 ± 3% of that observed during control breaths (p&lt;0.01) whereas PA activity was little changed (105 ± 5%; NS). EI instantaneous SMU peak firing frequency (PFF) was also greater during the occluded breath (15.7 ± 1.6Hz vs. 11.3 ± 0.3Hz; p&lt;0.05). whereas there was only a small increase in PA PFF (10.8 ± 0.6Hz vs. 10.0 ± 0.6Hz; NS).SummaryHF‐SCS during airway occlusion results in significant increases in activation of the EI but not PA muscles.ConclusionHF‐SCS applied to support ventilation in high tetraplegics with airway obstruction may elicit compensatory increases in EI muscle activation. These results support the concept that spinal reflex effects remain functional during HF‐SCS. The EI have a much higher density of muscle spindles compared to the PA muscles, which may mediate the differential activation of these muscles.

Resistance Breathing and Sympathetic Nerve Activity During Simulated Hemorrhage in Humans

BackgroundResistance breathing amplifies the respiratory pump during inspiration, so may be an effective intervention for treatment of hemorrhagic injuries. In animal studies of actual hemorrhage, and human studies of simulated hemorrhage, resistance breathing protects arterial pressure, and improves tolerance to this stress. Anecdotally, resistance breathing also increases the coupling between sympathetic nerve activity and arterial pressure. The impact of resistance breathing on overall sympathetic nerve activity, however, has not been examined. We tested the hypothesis that resistance breathing increases sympathetic nerve activity during simulated hemorrhage in healthy humans.MethodsLower body negative pressure (LBNP) was used to simulate hemorrhage in five human subjects (3M, 2F; 29.2 ± 6.8 y). Two experiments were conducted (randomized order): 1) a control condition in which LBNP was applied at 3 mmHg/min until the onset of presyncope, and 2) a resistance breathing condition in which the same LBNP protocol was used, but subjects breathed through a resistance device (set at ‐7 cm.H2O) during the final stages of the protocol. Arterial pressure and muscle sympathetic nerve activity (MSNA) of the radial nerve were monitored continuously. Bursts frequency (bursts/min) and burst incidence (burst/ 100 heart beats) were used to quantify MSNA. Coupling between diastolic arterial pressure (DAP) and MSNA was assessed by transfer function analysis coherence within the low frequency range (0.04‐0.15 Hz). Two‐way repeated measures ANOVAs were conducted for assessment of responses in the control and resistance breathing conditions, between baseline and at matched time points late in the LBNP protocol.ResultsWhile LBNP induced increases in both MSNA burst frequency (P=0.003) and burst incidence (P=0.06), there was no effect of resistance breathing on MSNA for either index during LBNP (control, 57.9 ± 25.9 bursts/min vs. resistance breathing, 50.6 ± 21.7 bursts/min, P=0.99; control, 55.6 ± 25.6 b/100 heart beats vs. resistance breathing, 42.3 ± 18.3 b/100 heart beats, P=0.42). Additionally, there was no effect of resistance breathing on DAP (control, 73.2 ± 9.9 mmHg vs. resistance breathing, 72.8 ± 4.4 mmHg; P=0.99), or coherence between MSNA and DAP during LBNP (control, 0.53 ± 0.21 vs. resistance breathing, 0.69 ± 0.17; P=0.46).ConclusionContrary to our hypothesis, resistance breathing had no effect on sympathetic nerve activity during LBNP. A limitation of this study is the low sample size (N=5), and high variability of MSNA. Future investigations with a larger sample size are needed to determine if respiratory dynamics can influence the coupling between MSNA and arterial pressure.