Effectiveness of pulmonary rehabilitation programmes and/or respiratory muscle training in patients with post-COVID conditions: a systematic review.

BACKGROUND: The term "post-COVID-19 condition" refers to the symptomatology that appears between four to twelve weeks after Covid-19 infection. These symptoms can persist for weeks or even months, significantly diminishing the quality of life for affected individuals. The primary objective of this study was to assess the effectiveness of pulmonary rehabilitation programs and/or respiratory muscle training on respiratory sequelae in patients with post-COVID condition. METHODS: The literature search was conducted in the following databases: PubMed, PEDro, Embase, Cochrane, Scopus, and Web of Science. Randomized clinical trials were included in which participants were aged 18 years or older. Articles were excluded if at least one of the therapies did not involve pulmonary rehabilitation or respiratory muscle training, if the participants were COVID positive, if studies lacked results, and finally, if interventions were conducted without supervision or at home. This review only encompasses supervised non-virtual interventions. This study adheres to the PRISMA statement and has been registered in the PROSPERO database (CRD42023433843). RESULTS: The outcomes obtained in the included studies are assessed across the following variables: Exercise capacity using the 6-minute walk test, Dyspnea, fatigue, Pulmonary function, Maximum inspiratory pressure, and Quality of life. CONCLUSION: Despite the absence of a specific treatment at present, it was evident from this review that a well-structured pulmonary rehabilitation program that incorporates both aerobic and muscular strength exercises along with techniques and inspiratory muscle exercises was the most effective form of treatment.

Practice effects of a breathing technique on pilots' cognitive and stress associated heart rate variability during flight operations.

Commercial pilots endure multiple stressors in their daily and occupational lives which are detrimental to psychological well-being and cognitive functioning. The Quick coherence technique (QCT) is an effective intervention tool to improve stress resilience and psychophysiological balance based on a five-minute paced breathing exercise with heart rate variability (HRV) biofeedback. The current research reports on the application of QCT training within an international airline to improve commercial pilots' psychological health and support cognitive functions. Forty-four commercial pilots volunteered in a one-month training programme to practise self-regulated QCT in day-to-day life and flight operations. Pilots' stress index, HRV time-domain and frequency-domain parameters were collected to examine the influence of QCT practice on the stress resilience process. The results demonstrated that the QCT improved psychophysiological indicators associated with stress resilience and cognitive functions, in both day-to-day life and flight operation settings. HRV fluctuations, as measured through changes in RMSSD and LF/HF, revealed that the resilience processes were primarily controlled by the sympathetic nervous system activities that are important in promoting pilots' energy mobilization and cognitive functions, thus QCT has huge potential in facilitating flight performance and aviation safety. These findings provide scientific evidence for implementing QCT as an effective mental support programme and controlled rest strategy to improve pilots' psychological health, stress management, and operational performance.

The effect of respiratory muscle training on respiratory muscle strength, diaphragm thickness/mobility, and exercise capacity in patients with systemic lupus erythematosus and associated shrinking lung syndrome.

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder that can impact any organ in the body. The pathophysiology of shrinking lung syndrome (SLS), a rare pulmonary complication of SLE, remains unknown. The objective of the current case series was to investigate the effects of inspiratory muscle training (IMT) on diaphragm thickness/mobility, respiratory muscle strength, peripheral muscle thickness/strength, and functional exercise capacity in patients with SLE and associated SLS. Three patients with SLE were included in the case series. Respiratory muscle strength, peripheral muscle strength, peripheral muscle thickness, diaphragm muscle thickness, diaphragm muscle mobility, functional exercise capacity, and pulmonary function test were assessed. A significant improvement has been determined in respiratory muscle strength, functional exercise capacity, peripheral muscle strength, peripheral muscle thickness, diaphragm muscle thickness, and diaphragm muscle mobility. This is the first case series showing the beneficial effects of IMT on respiratory muscle strength, diaphragm thickness/mobility, peripheral muscle thickness/strength, and exercise capacity in patients with SLE.

Interoceptive awareness mediated the effects of a 15-minute diaphragmatic breathing on empathy for pain: A randomized controlled trial.

Although empathy for pain plays an important role in positive interpersonal relationships and encourages engagement in prosocial behavior, it remains largely unknown whether empathy for pain could be effectively altered by psychophysiological techniques. This study aimed to investigate the impact of a single session of diaphragmatic breathing practice on empathy for pain and examine the potential mechanism involving interoceptive awareness. A total of 66 healthy participants were randomly assigned to the intervention group or the control group. The intervention group received a 15-minute diaphragmatic breathing (DB) practice with real-time biofeedback, while the control group was to gaze at a black screen at rest and not engaged in any other activities. Before and after the invention, all participants were instructed to evaluate the intensity and unpleasantness of empathy for pain while watching different pictures with pain or non-pain conditions. The Multidimensional Assessment of Interoceptive Awareness (MAIA) was then administered to measure interoceptive awareness. The results indicated a significant interaction between group and time with regard to empathy for pain and MAIA. The DB group showed a statistically significant decrease in both pain intensity and unpleasantness during the pain picture condition, as well as a noteworthy increase in MAIA scores. The control group did not demonstrate any substantial changes. More importantly, the regulation of attention, a dimension of MAIA, had a significant mediating effect on the impact of diaphragmatic breathing on reported unpleasantness. Diaphragmatic breathing could serve as a simple, convenient, and practical strategy to optimize human empathy for pain that warrants further investigation, which has important implications not only for individuals with impaired empathy for pain but also for the improvement of interoceptive awareness.

The effect of 20-minute mindful breathing exercise on psychological well-being in epilepsy: A pilot randomized controlled trial.

INTRODUCTION: Depression and anxiety are prevalent in epilepsy patients, but psychiatric or psychological services may not be accessible to all patients. This study aimed to determine the effectiveness of the 20-minute mindful breathing on the psychological well-being of PWE using an instructional video. METHOD: This was a pilot, assessor-blinded, randomized controlled trial. The intervention group received a guided video and was briefed to perform the exercise twice a week for two weeks while the waitlist control group only received the video upon completion of the study. The subjects were assessed at three-time points (T0: Baseline, T1: 2 weeks after the intervention, T2: 4 weeks after intervention), using the Neurological Disorders Depression Index (NDDI-E), General Anxiety Disorder (GAD-7), Quality of Life in Epilepsy Inventory (QOLIE-31) and Mindfulness Attention Awareness Scale (MAAS). RESULTS: Twenty patients were recruited, with 10 in the intervention and waitlist-control groups. Compared with the waitlist-control group, participants in the intervention group showed significant improvement in NDDI-E at T1 (p = 0.022) but not at T2 (p = 0.056) and greater improvement in GAD-7 at T1 and T2 but not statistically significant. The QOLIE-31 overall score in the intervention group has significantly improved at T1 (p = 0.036) and T2 (p = 0.031) compared to the waitlist-control group. For MAAS, the intervention group also had an increased score at T2 (p = 0.025). CONCLUSION: The 20-minute mindfulness breathing exercise has an immediate effect in improving depression and quality of life among people with epilepsy.

Breathing control training for functional seizures: A multi-site, open-label pilot study.

There are no well-validated treatments for functional seizures. While specialist psychotherapy is usually recommended, the evidence for its benefit is qualified, and it can be difficult to obtain. Given the association between hyperventilation and functional seizures we explored an alternative modality, breathing control training, in a multi-site open label pilot trial. Participants with functional seizures over the age of 16 received an hour of breathing training from a respiratory physiotherapist, with a half-hour booster session a month later. Seizure frequency and Nijmegen scores (a measure of hyperventilation) were reported at baseline and follow-up, 3-4 months later. Eighteen subjects were recruited, and 10 completed follow-up. Seven of these 10 had improved seizure frequency, and 3 did not (Wilcoxon signed rank test, p = 0.09), with seizure frequency correlating with Nijmegen score (Spearman's rank correlation = 0.75, p = 0.034). The intervention was well tolerated, with no adverse events reported. These preliminary results support a potentially new approach to treating functional seizures that should prove cost-effective and acceptable, though require confirmation by a randomised controlled trial.

Nonpharmacological treatment of rumination syndrome in childhood: A systematic review of the literature.

Rumination syndrome (RS) is a complex functional disorder characterized by recurrent, repetitive regurgitation of recently swallowed food. RS may have medical and psychosocial implications, compromising the quality of life and causing high rates of school absenteeism. Pediatric RS has been poorly studied and little evidence regarding its treatment is available. This systematic review aims to evaluate the literature on the nonpharmacological treatment of RS in childhood. A systematic literature search was conducted on MEDLINE/PubMed, CINAHL, Cochrane Library, PsycINFO, and PEDro, from 2000 to 2023. The methodological quality of the publications was assessed by applying the guidelines proposed by the Equator network, according to the different designs of study, and the risk of bias was evaluated with the Risk Of Bias In Non-Randomized Studies of Interventions (ROBINS-I). Five hundred ninety-six studies were screened, and 7 studies were included in the review. Diaphragmatic breathing was the most used nonpharmacological treatment, and it was always combined with other therapeutic strategies. The vast heterogeneity of the physical or mental comorbidities and the methodology adopted in the publications did not allow a comparative analysis of the different treatments. Regardless of the type of treatment, high-intensity therapeutic programs and specific operators' training emerged as the most influencing factors for patients' outcomes. According to the available evidence, there is not enough high-quality evidence to suggest a defined therapeutic strategy. Large observational studies on selected patients accounting for possible confounders, with adequate follow-up times, and with clearly defined treatment regimens are needed to identify the best therapeutic approach.

Enhancement of Pulmonary Function and Reduction of Complications Through EIT-Guided Yoga Breathing Exercise After Esophagectomy.

BACKGROUND This study aimed to investigate the impact of EIT-guided yoga breathing training on postoperative pulmonary complications (PPCs) for esophageal cancer patients. MATERIAL AND METHODS Total of 62 patients underwent radical resections of esophageal cancer. Esophageal cancer patients were randomized to the standard care group, or the intervention group receiving an additional complete breathing exercise under the guidance of EIT in AICU. Following extubation after the esophagectomy, pulmonary functions were evaluated by EIT with center of ventilation (CoV), dependent silent spaces (DSS), and non-dependent silent spaces (NSS). RESULTS Sixty-one older esophageal cancer patients (31 in the Control group and 30 in the EIT group) were included in the final analysis. Forty-four patients experienced pulmonary complications after esophagectomy, 27 (87.1%) in the Control group and 17 (36.7%) in the EIT group (RR, 0.42 (95% CI: 0.26, 0.69). The most common pulmonary complication was pleural effusion, with an incidence of 30% in the EIT group and 74.2% in the Control group, with RR of 0.40 (95% CI: 0.23, 0.73). Time for the first pulmonary complication was significantly longer in the EIT group than in the Control group (hazard ratio, HR, 0.43; 95% CI 0.21 to 0.87; P=0.019). Patients in the EIT group had significantly higher scores in CoV, DSS, and NSS than in the Control group. CONCLUSIONS Guided by EIT, the addition of the postoperative breathing exercise to the standardized care during AICU could further improve pulmonary function, and reduce postoperative pulmonary complications after esophagectomy.

Effects of Breathing Exercises in Patients With Chronic Obstructive Pulmonary Disease: A Network Meta-analysis.

OBJECTIVE: A network meta-analysis of randomized controlled trials (RCTs) was conducted to compare and rank the effectiveness of various breathing exercises for patients with chronic obstructive pulmonary disease (COPD). DATA SOURCES: We searched PubMed, Web of Science, Embase, and the Cochrane Library databases to determine the articles. STUDY SELECTION: Publications investigating the effect of breathing exercises on exercise capacity (six-minute walk test [6MWT]), pulmonary function (the ratio of the first second forced expiratory volume of forced vital capacity [FEV1/FVC]), quality of life (St George's Respiratory Questionnaire [SGRQ]), inspiratory muscle pressure (maximum inspiratory pressure [PImax]), and dyspnea (Borg scale) were searched. DATA EXTRACTION: Data extracted by 2 researchers were entered into predesigned tables for data extraction. The quality of the literature was assessed using the Cochrane Collaboration's tool. DATA SYNTHESIS: A total of 43 RCTs involving 1977 participants were analyzed. To boost exercise capacity, the top 2 exercises were inspiratory muscle training (75%), Chinese traditional fitness exercises (13%); To improve pulmonary function, the top 2 exercises were Chinese traditional fitness exercises (32%), diaphragm breathing (30%); To raise patients' quality of life, the top 2 exercises were yoga (52%), diaphragm breathing (28%); To increase inspiratory muscle pressure, the top 2 exercises were pursed-lip breathing (47%), Chinese traditional fitness exercises (25%); To improve dyspnea, the top 2 exercises were yoga (44%), inspiratory muscle training (22%). CONCLUSIONS: Various breathing exercises for COPD patients confer benefits that manifest in diverse ways. Pulmonary rehabilitation specialists could administer personalized breathing exercises tailored to each patient's condition to attain optimal therapeutic outcomes.

Effectiveness of Rehabilitation Interventions on Adults With COVID-19 and Post-COVID-19 Condition. A Systematic Review With Meta-analysis.

OBJECTIVE: To evaluate the effectiveness of rehabilitation interventions for adults with COVID-19 and post COVID-19 condition (PCC) in all settings. DATA SOURCES: PubMed, EMBASE, CINAHL, Scopus, Web of Science, and Physiotherapy Evidence Database were searched from inception to December 31st, 2021. PROSPERO registration number: CRD42021258553. STUDY SELECTION: We included randomized controlled trials (RCTs) and non-randomized studies of interventions (NRSI) according to the University of Alberta Evidence-based Practice Center. DATA EXTRACTION: One author extracted data using a predetermined Excel form. DATA SYNTHESIS: The meta-analysis indicates uncertain evidence about the effect of pulmonary rehabilitation and self-activities on exercise capacity (MD 65.06, 95% CI 42.87 to 87.25), respiratory function (forced expiratory volume in the first second [FEV1]: MD 0.16, 95% CI 0.05 to 0.28; FEV1/forced vital capacity [FVC]: MD 0.05, 95% CI 0.01 to 0.09; FVC: MD 0.19, 95% CI -0.03 to 0.42) and anxiety (MD -12.03, 95% CI -21.16 to -2.90) in mild COVID-19 and PCC patients. According to the narrative synthesis, including RCTs and NRSI, prone positioning seems to show improvements in vital parameters in severe COVID-19 post intensive care unit (ICU) discharge, pulmonary rehabilitation in activities of daily living, and qigong exercise and acupressure rehabilitation program, and "twist and raise" walking technique in reducing dyspnea and weakness in any degree of severity of COVID-19 and PCC. Functional electrical stimulation-cycling or early rehabilitation programs seem to support a faster recovery in patients with moderate COVID-19 after ICU discharge. Yoga and naturopathy, Mandala coloring, and respiratory exercise seem to reduce anxiety and depression in patients with moderate and mild COVID-19. Cognitive motor training seems to improve cognitive function in PCC patients. CONCLUSIONS: There is very uncertain evidence about the effect of pulmonary rehabilitation on exercise capacity and respiratory function in patients with mild COVID-19 and PCC. Further high-quality research is required to improve the certainty of evidence available to support rehabilitation's crucial role in managing COVID-19.

Effects of different inspiratory muscle training protocols on functional exercise capacity and respiratory and peripheral muscle strength in patients with chronic kidney disease: a randomized study.

BACKGROUND: Pathological changes were observed in the diaphragm due to abnormal renal function in chronic kidney disease (CKD). Inspiratory muscle training (IMT) has been suggested for patients with CKD; however, the most appropriate intensity for IMT has not been determined. Therefore, this study aimed to investigate the effects of different IMT protocols on respiratory muscle strength, quadriceps femoris muscle strength (QMS), handgrip muscle strength (HGS), functional exercise capacity, quality of life (QoL), pulmonary function, dyspnoea, fatigue, balance, and physical activity (PA) levels in patients with CKD. METHODS: This randomized, controlled, single-blind study included 47 patients and they were divided into three groups: Group 1 (n = 15, IMT with 10% maximal inspiratory pressure (MIP)), Group 2 (n = 16, IMT with 30% MIP), and Group 3(n = 16; IMT with 60% MIP). MIP, maximal expiratory pressure (MEP), 6-min walking test (6-MWT), QMS, HGS, QoL, pulmonary function, dyspnoea, fatigue, balance, and PA levels were assessed before and after eight weeks of IMT. RESULTS: Increases in MIP, %MIP, 6-MWT distance, and %6-MWT were significantly higher in Groups 2 and 3 than in Group 1 after IMT (p < 0.05). MEP, %MEP, FEF25-75%, QMS, HGS, and QoL significantly increased; dyspnoea and fatigue decreased in all groups (p < 0.05). FVC, PEF, and PA improved only in Group 2, and balance improved in Groups 1 and 2 (p < 0.05). CONCLUSIONS: IMT with 30% and 60% MIP similarly improves inspiratory muscle strength and functional exercise capacity. IMT with 30% is more effective in increasing PA. IMT is a beneficial method to enhance peripheral and expiratory muscle strength, respiratory function, QoL and balance, and reduce dyspnoea and fatigue. IMT with %30 could be an option for patients with CKD who do not tolerate higher intensities. TRIAL REGISTRATION: This study was retrospectively registered (NCT06401135, 06/05/2024).

Effectiveness of Rehabilitation Interventions in Individuals With Emerging Virtual Respiratory Tract Infectious Disease: A Systematic Review and Meta-Analysis.

OBJECTIVE: Assessing rehabilitation effectiveness for persistent symptoms post-infection with emerging viral respiratory diseases. DATA SOURCES: Systematic review of seven databases (MEDLINE, EMBASE, Cochrane Library, PEDro, MedRxiv, CNKI, Wanfang) until 30 December 2023. REVIEW METHODS: Evaluated 101 studies (9593 participants) on respiratory function, exercise capacity, and quality of life. Methodological quality was assessed using the Cochrane Collaboration's Risk of Bias tool for randomized controlled trials (RCTs), the Newcastle-Ottawa Scale (NOS) for observational studies and non-RCTs, and the NIH Quality Assessment Tools for before-after studies. RESULTS: The most common rehabilitation program combined breathing exercises with aerobic exercise or strength training. Rehabilitation interventions significantly enhanced respiratory function, as evidenced by improvements on the Borg Scale (MD, -1.85; 95% CI, -3.00 to -0.70, low certainty), the mMRC Dyspnea Scale (MD, -0.45; 95% CI, -0.72 to -0.18, low certainty), and the Multidimensional Dyspnoea-12 Scale (MD, -4.64; 95% CI, -6.54 to -2.74, moderate certainty). Exercise capacity also improved, demonstrated by results from the Six-Minute Walk Test (MD, 38.18; 95% CI, 25.33-51.03, moderate certainty) and the Sit-to-Stand Test (MD, 3.04; 95% CI, 1.07-5.01, low certainty). CONCLUSION: Rehabilitation interventions are promising for survivors of viral respiratory diseases, yet gaps in research remain. Future investigations should focus on personalizing rehabilitation efforts, utilizing remote technology-assisted programs, improving research quality, and identifying specific subgroups for customized rehabilitation strategies to achieve the best outcomes for survivors.

The effect of respiratory muscle training on children and adolescents with cystic fibrosis: a systematic review and meta-analysis.

BACKGROUND: Cystic fibrosis is a chronic genetic disease that can affect the function of the respiratory system. Previous reviews of the effects of respiratory muscle training in people with cystic fibrosis are uncertain and do not consider the effect of age on disease progression. This systematic review aims to determine the effectiveness of respiratory muscle training in the clinical outcomes of children and adolescents with cystic fibrosis. METHODS: Up to July 2023, electronic databases and clinical trial registries were searched. Controlled clinical trials comparing respiratory muscle training with sham intervention or no intervention in children and adolescents with cystic fibrosis. The primary outcomes were respiratory muscle strength, respiratory muscle endurance, lung function, and cough. Secondary outcomes included exercise capacity, quality of life and adverse events. Two review authors independently extracted data and assessed study quality using the Cochrane Risk of Bias Tool 2. The certainty of the evidence was assessed according to the GRADE approach. Meta-analyses where possible; otherwise, take a qualitative approach. RESULTS: Six studies with a total of 151 participants met the inclusion criteria for this review. Two of the six included studies were published in abstract form only, limiting the available information. Four studies were parallel studies and two were cross-over designs. There were significant differences in the methods and quality of the methodology included in the studies. The pooled data showed no difference in respiratory muscle strength, lung function, and exercise capacity between the treatment and control groups. However, subgroup analyses suggest that inspiratory muscle training is beneficial in increasing maximal inspiratory pressure, and qualitative analyses suggest that respiratory muscle training may benefit respiratory muscle endurance without any adverse effects. CONCLUSIONS: This systematic review and meta-analysis indicate that although the level of evidence indicating the benefits of respiratory muscle training is low, its clinical significance suggests that we further study the methodological quality to determine the effectiveness of training. TRIAL REGISTRATION: The protocol for this review was recorded in the International Prospective Register of Systematic Reviews (PROSPERO) under registration number CRD42023441829.

The effect of breathing exercises and mindset with or without cold exposure on mental and physical health in persons with a spinal cord injury-a protocol for a three-arm randomised-controlled trial.

STUDY DESIGN: A three-arm randomized controlled trial. OBJECTIVES: To investigate the effects of the Wim Hof Method (WHM), with (WHM-C) and without cold exposure (WHM-NC), on mental and physical health in persons with chronic spinal cord injury (SCI). SETTING: Rehabilitation centre (assessments and once-weekly intervention sessions) and home-based (daily intervention sessions). METHODS: Sixty adults with chronic SCI will be randomised (1:1:1) to one of three groups: participants in the intervention groups (i.e., WHM-C and WHM-NC) will engage in a 7-week intervention, with one weekly practice session at the rehabilitation centre and a daily WHM session at home. WHM-NC will consist of breathing exercises and mindset, while participants in WHM-C will partake in breathing exercises, mindset and cold exposure. Participants allocated to usual care (UC) will not receive the WHM intervention. The primary outcome is mental health reported via the Mental Health Inventory (MHI)-5, while secondary outcomes include circulating inflammatory and metabolic marker concentration, pulmonary function, body composition, sleep quality, spasticity, chronic pain and psychological stress. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the medical ethics committee of the Máxima Medical Centre (Veldhoven, the Netherlands; identifier: w22.069). If shown efficacious in improving mental health, as well as physical health, in persons with chronic SCI, the low cost and accessibility of the WHM allows it to be directly implemented in SCI rehabilitation. TRIAL REGISTRATION NUMBER: NCT05704322.

Creatine supplementation combined with breathing exercises reduces respiratory discomfort and improves creatine status in patients with long-COVID.

ABSTRACT: Eight long-COVID patients with moderate fatigue that had lasted for ≥3 months were recruited. All patients were allocated in a double-blind parallel-group design to receive either 4 g of creatine per day plus breathing exercises (study group) or breathing exercises only (control group) for 3 months. Creatine induced a significant increase in tissue total creatine levels for all 14 locations evaluated in the present study ( P < 0.05), while its levels significantly dropped in the right frontal gray matter and left parietal mesial gray matter at follow-up in the control group ( P < 0.05). No change in time to exhaustion was demonstrated in the control group (P > 0.05), while the mean time to exhaustion was significantly improved for 54 s in the study group post-administration (P = 0.05). These preliminary findings suggest that creatine is as an effective adjuvant therapeutic to breathing exercises for tackling the clinical features in long-COVID.

Breathing life into social emotional learning programs: A Bio-Psycho-Social approach to risk reduction and positive youth development.

INTRODUCTION: Over one-third of US adolescents engage in health risk and problem behaviors. Additionally, significant percentages of problem-free youth aren't flourishing. Left unaddressed, the lifetime mental/physical health and financial burdens may be substantial. Social-Emotional Learning (SEL) and Positive Youth Development (PYD) programs have proliferated to address the drivers of adaptive versus risk behaviors. Research suggests SEL/PYD program outcomes can be improved by adding techniques that physiologically induce calmness, yet few studies exist. METHODS: This randomized controlled trial of 79 urban eighth-graders examined a standardized bio-psycho-social program, SKY Schools, which incorporates a physiologically calming component: controlled yogic breathing. RESULTS: Repeated-measures ANOVAs demonstrated that compared to controls, SKY graduates exhibited significant improvements in emotion regulation, planning and concentration, and distractibility. After 3 months, significant improvements were evidenced in emotion regulation, planning and concentration, identity formation, and aggressive normative beliefs. CONCLUSION: SEL/PYD programs may benefit by incorporating biologically-calming techniques to enhance well-being and prevent risk/problem behaviors.

The Application of Self-Made Disseminating and Descending Breathing Exercises in Home Rehabilitation of Stable COPD.

To investigate the clinical effects and application value of self-made disseminating and descending breathing exercises on home rehabilitation of patients with stable chronic obstructive pulmonary disease (COPD). Seeking to generate concepts for creating novel, convenient, and efficient COPD prognosis rehabilitation exercises aimed at enhancing the well-being and rehabilitation confidence of both COPD patients and their families. A total of 70 COPD patients admitted to our outpatient department from July 2019 to September 2021 were randomly divided into the exercise group (n = 35) and the control group (n = 35). The control group received routine breathing training, while the exercise group was treated with self-made disseminating and descending breathing exercises. The respiratory function, including pulmonary function (FVC, FEV1, FEV1/FVC) and respiratory muscle strength (MIP, MEP), exercise tolerance (6-min walking distance, 6MWT), Modified Medical Research Council Dyspnea Scale (mMRC, Borg), COPD quality of life score (CAT, SGRQ), anxiety and depression scores (HAMA, HAMD) were compared between the two groups after 12-week exercise. After 12-week training, the FEV1, MIP, and MEP in the exercise group were significantly higher than those in the control group (p < 0.001), and the 6MWT was significantly increased in the exercise group compared to the control group (p < 0.001); while the mMRC, Borg score, the scores of CAT, SGRQ, HAMA, and HAMD were found significantly lower than those in the control group (p < 0.001). The self-made disseminating and descending breathing exercises can improve respiratory function and reduce symptoms of dyspnea in COPD patients, while enhancing exercise tolerance and relieving anxiety and depression, and are worthy of clinical application.

Virtual Reality Breathing Interventions for Mental Health: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Breathing exercises have been shown to reduce mental health problems among clinical and non-clinical populations. Although virtual reality (VR) breathing interventions are assumed to have potential benefits, it remains unclear whether VR breathing interventions are more effective at improving mental health than non-VR breathing interventions. We conducted a systematic literature search in six electronic databases (Web of Science, PsycINFO, Embase, Cochrane Central Register of Controlled Trials, Scopus, and PubMed) from inception to 30th September, 2022. We included randomized controlled trials in adults evaluating effects of VR compared to non-VR breathing interventions on primary outcomes of mental health (stress, anxiety and mood), and secondary outcomes of physiological stress measures (e.g., heart rate (HR), heart rate variability (HRV)). Within these selected studies, we explored differences in likeability and future use between VR and non-VR breathing interventions. 2.848 records were identified of which 65 full-text articles were assessed. Six RCTs were included, of which five were suitable for meta-analyses. Comparing VR to non-VR breathing interventions, there were no significant differences in overall mental health, stress, anxiety or mood, nor in HR or HRV. There was no evidence that participants liked VR breathing interventions more than non-VR, nor would use them more in the future. These results suggest that there is no evidence that VR breathing interventions are more effective than non-VR in improving mental health outcomes, HR, HRV. Further research is required to determine whether there may be advantages to longer-term VR-implementation and practice, and explore possible mechanisms.

Influence of Respiratory Frequency of Slow-Paced Breathing on Vagally-Mediated Heart Rate Variability.

Breathing techniques, particularly slow-paced breathing (SPB), have gained popularity among athletes due to their potential to enhance performance by increasing cardiac vagal activity (CVA), which in turn can help manage stress and regulate emotions. However, it is still unclear whether the frequency of SPB affects its effectiveness in increasing CVA. Therefore, this study aimed to investigate the effects of a brief SPB intervention (i.e., 5 min) on CVA using heart rate variability (HRV) measurement as an index. A total of 75 athletes (22 female; Mage = 22.32; age range = 19-31) participated in the study, attending one lab session where they performed six breathing exercises, including SPB at different frequencies (5 cycles per minute (cpm), 5.5 cpm, 6 cpm, 6.5 cpm, 7 cpm), and a control condition of spontaneous breathing. The study found that CVA was significantly higher in all SPB conditions compared to the control condition, as indexed by both root mean square of the successive differences (RMSSD) and low-frequency HRV (LF-HRVms2). Interestingly, LF-HRVms2 was more sensitive in differentiating the respiratory frequencies than RMSSD. These results suggest that SPB at a range of 5 cpm to 7 cpm can be an effective method to increase CVA and potentially improve stress management and emotion regulation in athletes. This short SPB exercise can be a simple yet useful tool for athletes to use during competitive scenarios and short breaks in competitions. Overall, these findings highlight the potential benefits of incorporating SPB into athletes' training and competition routines.

Do Longer Exhalations Increase HRV During Slow-Paced Breathing?

Slow-paced breathing at an individual's resonance frequency (RF) is a common element of heart rate variability (HRV) biofeedback training (Laborde et al. in Psychophysiology 59:e13952, 2022). Although there is strong empirical support for teaching clients to slow their respiration rate (RR) to the adult RF range between 4.5 and 6.5 bpm (Lehrer & Gevirtz, 2014), there have been no definitive findings regarding the best inhalation-to-exhalation (IE) ratio to increase HRV when breathing within this range. Three methodological challenges have frustrated previous studies: ensuring participants breathed at the target RR, IE ratio, and the same RR during each IE ratio. The reviewed studies disagreed regarding the effect of IE ratios. Three studies found no IE ratio effect (Cappo & Holmes in J Psychosom Res 28:265-273, 1984; Edmonds et al. in Biofeedback 37:141-146, 2009; Klintworth et al. in Physiol Meas 33:1717-1731, 2012). One reported an advantage for equal inhalations and exhalations (Lin et al. in Int J Psychophysiol 91:206?211, 2014). Four studies observed an advantage for longer exhalations than inhalations (Bae et al. in Psychophysiology 58:e13905, 2021; Laborde et al. in Sustainability 13:7775, 2021; Strauss-Blasche et al. in Clin Exp Pharmacol Physiol 27:601?60, 2000; Van Diest et al. in Appl Psychophysiol Biofeedback 39:171?180, 2014). One study reported an advantage for longer inhalations than exhalations (Paprika et al. in Acta Physiol Hung 101:273?281, 2014). We conducted original (N = 26) and replication (N = 16) studies to determine whether a 1:2 IE ratio produces different HRV time-domain, frequency-domain, or nonlinear metrics than a 1:1 ratio when breathing at 6 bpm. Our original study found that IE ratio did not affect HRV time- and frequency-domain metrics. The replication study confirmed these results and found no effect on HRV nonlinear measurements.