European Journal of Cardiovascular Medicine

Cardiovascular and respiratory diseases remain leading causes of morbidity and mortality worldwide, and non-pharmacological interventions that modulate autonomic balance and respiratory mechanics are of growing interest as adjunctive strategies for prevention and rehabilitation. Mindfulness and meditation programs, together with slow-paced and structured breathing techniques, have been proposed to influence cardiovascular regulation (blood pressure, heart rate, heart-rate variability) and respiratory function (respiratory rate, lung volumes, peak expiratory flows) through autonomic, hemodynamic and central-neural mechanisms. Recent quantitative syntheses of randomized trials report small-to-moderate reductions in systolic and diastolic blood pressure associated with meditation interventions, supporting potential cardiovascular benefit beyond psychological outcomes [1]. Randomized clinical trials of standardized mindfulness programs targeting people with elevated blood pressure have likewise demonstrated clinically meaningful reductions in office and ambulatory blood pressure alongside improvements in psychological stress and quality of life [2].

Mechanistic and experimental research suggests that the physiological effects of meditation and breath-focused practices are mediated largely by modulation of autonomic control and cardiorespiratory coupling. Slow or paced breathing at or near an individual’s resonance frequency reliably increases vagally-mediated heart-rate variability and baroreflex sensitivity, and can acutely reduce sympathetic outflow and lower systolic blood pressure in healthy and clinical populations [3–5]. Converging reviews and practical guides for resonance-frequency assessment emphasize that regular practice of slow-paced breathing amplifies respiratory sinus arrhythmia and improves temporal coherence between respiration, blood pressure and cardiac rhythms — a plausible pathway for both short-term and sustained autonomic benefits [3,4].

Beyond autonomic modulation, structured breathing (including yogic pranayama) has been proposed to affect respiratory mechanics, chemoreceptor and mechanoreceptor signalling, and central respiratory control circuits; these changes can translate into measurable improvements in pulmonary function and symptom control in both healthy subjects and respiratory disease cohorts [6]. Despite accumulating evidence, heterogeneity in interventions (meditation type, breathing protocol, dose), outcome measures (office vs ambulatory blood pressure, HRV indices, FEV1/FVC, PEFR), and study populations complicates synthesis. Therefore, we performed a systematic review to synthesize randomized and controlled evidence on the effects of meditation, mindfulness, and breath-focused interventions on cardiorespiratory physiological parameters (blood pressure, heart rate/HRV, respiratory rate, tidal volume and standard pulmonary function indices) and to identify gaps for future trials.

Study Design and Registration: This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines [7]. The protocol was conceptualized prior to initiation of the literature search and aimed to summarize the evidence on the effects of meditation and meditation-based practices on cardio-respiratory parameters in human participants.

Search Strategy: An extensive electronic search was performed in PubMed, Scopus, Web of Science, and Google Scholar databases for published articles. The search was designed using both MeSH terms and free-text keywords, combined with Boolean operators: (“meditation” OR “mindfulness” OR “yoga” OR “pranayama” OR “breathing exercise”) AND (“cardiovascular” OR “cardiorespiratory” OR “heart rate” OR “blood pressure” OR “heart rate variability” OR “respiratory rate” OR “FEV1” OR “FVC” OR “PEFR”).

The search was limited to studies involving human participants and English-language publications. Reference lists of eligible articles and prior reviews were manually screened to identify additional studies not captured through database searches.

Eligibility Criteria: Studies were selected according to predefined inclusion and exclusion criteria:

• Inclusion criteria:
1. Randomized controlled trials (RCTs), controlled clinical trials, or observational studies (cross-sectional, cohort, or case-control).
2. Interventions explicitly describing meditation, mindfulness, or pranayama practices (either standalone or as part of yoga programs).
3. Reporting of at least one cardiovascular (e.g., heart rate, systolic/diastolic blood pressure, mean arterial pressure, heart rate variability) or respiratory parameter (e.g., FEV₁, FVC, PEFR, tidal volume, MVV, or respiratory rate).
4. Studies on adult human participants (≥18 years).
• Exclusion criteria:
1. Studies without a comparator or control group.
2. Reviews, editorials, commentaries, and non-original data reports.
3. Animal or in-vitro studies.
4. Studies assessing outcomes unrelated to cardiorespiratory physiology (e.g., psychological, metabolic, or biochemical parameters only).

Study Selection: All identified records were imported into EndNote 21 for deduplication. Two reviewers independently screened the titles and abstracts for relevance. Full-text articles of potentially eligible studies were assessed for inclusion. Any disagreements between reviewers were resolved through consensus with a third reviewer. A PRISMA 2020 flow diagram (Figure 1) was constructed to summarize the study selection process.

A total of 3,246 records were retrieved from electronic databases (PubMed, Scopus, Web of Science, and Google Scholar). After removing 812 duplicates, 2,434 articles underwent title and abstract screening. Of these, 137 full-text articles were assessed for eligibility. Following detailed evaluation, 19 studies met the inclusion criteria and were included in the final synthesis.

Figure 1: PRISMA flow diagram

Data Extraction: A structured data extraction sheet was used to collect details on author name, year of publication, country, study design, sample size, population characteristics, intervention type and duration, comparator, and primary cardio-respiratory outcomes (mean ± SD values where available). Data were extracted independently by two reviewers and cross-checked for accuracy.

Quality Assessment: The methodological quality of randomized controlled trials was assessed using the Cochrane Risk-of-Bias 2.0 (RoB 2) tool [8], evaluating domains such as randomization process, deviations from intended interventions, missing outcome data, measurement of outcomes, and selective reporting.For non-randomized interventional or observational studies, the ROBINS-I tool [9] was used. The ROBIS checklist [10] was applied to evaluate the credibility of included systematic reviews or meta-analyses.

Data Synthesis and Analysis: Given the anticipated heterogeneity across meditation modalities, participant populations, and outcome measures, a qualitative synthesis was planned. Where data homogeneity permitted, quantitative pooling would be considered using a random-effects meta-analysis model. Results were to be summarized as mean differences or standardized mean differences with 95% confidence intervals. Sensitivity analyses and subgroup assessments (e.g., mindfulness-based vs. breathing-focused meditation) were to be performed when feasible.

Across randomized and controlled trials, participation in structured mindfulness or meditation programs led to significant reductions in systolic and diastolic blood pressure, accompanied by improvements in emotional regulation and stress resilience (Table 1). Consistent benefits were observed in hypertensive, young adult, and coronary heart disease cohorts, with additional improvement in insulin sensitivity and overall cardiometabolic profile. Meta-analytic and systematic evidence further supported these findings, showing modest but statistically meaningful decreases in blood pressure and enhanced heart rate variability among long-term practitioners.

Controlled physiological and randomized designs consistently showed that slow or paced breathing increased baroreflex sensitivity and heart rate variability, while reducing blood pressure (Table 2). Pranayama techniques—including Bhrāmarī, OM chanting, and slow breathing—produced significant improvements in forced vital capacity (FVC), forced expiratory volume in one second (FEV₁), and peak expiratory flow rate (PEFR). These effects were also evident among individuals with asthma, chronic airflow limitation, and occupational exposure to pesticides, indicating both preventive and therapeutic potential for respiratory health.

Integrated yoga and combined mind–body practices (Table 3) revealed synergistic cardio-respiratory benefits. Multimodal interventions combining asanas, pranayama, and meditation led to reductions in resting heart rate and blood pressure alongside substantial improvement in pulmonary indices. Systematic reviews encompassing these modalities further reinforced their capacity to enhance autonomic balance, reduce stress markers, and optimize both cardiovascular and pulmonary efficiency.

Table 1. Mindfulness and Meditation-Based Interventions Targeting Cardiovascular Parameters

Table 2. Breathing and Pranayama-Focused Interventions with Respiratory and Autonomic Outcomes

Table 3. Integrated Yoga and Combined Mind–Body Interventions

This systematic synthesis found consistent evidence that structured mindfulness/meditation programs, paced-breathing and pranayama practices, and integrated yoga interventions exert measurable, complementary effects on cardio-respiratory physiology. The thematic grouping used in this review helps clarify that mindfulness-based programs primarily affect cardiovascular regulation and stress-related pathways, whereas breathing-focused techniques produce robust effects on autonomic reflexes and pulmonary mechanics; combined mind–body approaches show additive benefits across both domains. The discussion below places these findings in context, examines plausible mechanisms, acknowledges limitations of the current evidence base, and offers recommendations for future research and clinical translation.

Principal findings and comparison with broader literature: Mindfulness and meditation interventions in the cardiovascular-themed studies produced statistically and clinically meaningful reductions in systolic and diastolic blood pressure and improvements in measures of stress and emotion regulation (Table 1). These results align with broader mechanistic and interventional literature showing that interventions designed to increase parasympathetic tone or reduce sympathetic overactivity can lower blood pressure and improve cardiac autonomic markers. Heart-rate-variability biofeedback and resonance-frequency breathing — close physiological cousins of many breathing-centered meditation practices — reliably increase vagal indices of HRV and baroreflex gain, which are associated with better blood-pressure control and cardiovascular resilience [30–34]. Experimental studies that trained subjects in resonance-frequency or paced breathing report acute increases in low-frequency HRV power and baroreflex sensitivity, physiological changes that plausibly mediate at least part of the observed blood-pressure lowering effect [31,32,35].

Breathing and pranayama interventions produced consistent improvements in lung volumes, expiratory flows and respiratory muscle performance in both healthy volunteers and selected clinical groups. These effects are physiologically plausible: slow and controlled breathing increases tidal volume, reduces dead-space ventilation, optimises ventilatory patterning and improves gas-exchange efficiency, while repeated training strengthens respiratory muscles and improves airway mechanics [33,34]. Recent randomized and quasi-experimental work demonstrates that even relatively short training periods in resonance breathing or HRV biofeedback can translate to improved respiratory sinus arrhythmia and modest gains in spirometric parameters, particularly when interventions are supervised and of adequate duration [32,33].

Integrated yoga and multimodal mind–body programs combined advantages of both approaches and tended to show broader, synergistic benefits across autonomic and pulmonary outcomes. This is consistent with prior work showing that interventions combining posture, breath control and mindfulness produce system-level adaptations — improvements in cardiorespiratory coupling, reduced sympathetic drive, and enhanced ventilatory mechanics — more reliably than single-component interventions of very short duration [30,31].

Mechanistic interpretation: Two partially overlapping mechanisms likely underlie the observed effects. First, autonomic modulation: slow-paced breathing and meditative states enhance respiratory sinus arrhythmia and baroreflex sensitivity, increasing vagal outflow and reducing sympathetic tone; over time these changes can lower peripheral vascular resistance and resting heart rate, thereby reducing blood pressure. The resonance-frequency model explains why breathing at or near ~0.1 Hz maximizes HRV and baroreflex engagement, producing the largest autonomic gains per session [30,31,33]. Second, respiratory-mechanical adaptation: repeated practice of pranayama and controlled-breathing exercises increases diaphragmatic efficiency, respiratory muscle strength and expiratory flow dynamics, changes that manifest as higher FEV₁/FVC and PEFR in training studies and may improve symptoms in obstructive or exposure-related lung disease [32,34].

Clinical implications: The aggregated evidence suggests that meditation and breathing interventions can be considered adjunctive therapies for cardiovascular risk reduction and respiratory rehabilitation. For patients with elevated blood pressure, mindfulness-based programs and paced-breathing training may offer modest but meaningful reductions in systolic and diastolic pressures that complement pharmacotherapy and lifestyle measures. For respiratory impairments (e.g., asthma, chronic airflow limitation, occupational exposure), supervised pranayama and breathing-focused yoga may improve pulmonary function and quality of life when used alongside standard medical care. However, clinicians should prescribe these practices in structured formats (trained instructor, adherence monitoring, integration with usual care) because supervised, protocolized interventions show the most reliable physiological effects [33,35].

Methodological limitations and sources of heterogeneity: Despite encouraging results, several limitations of the current literature warrant caution. First, heterogeneity in interventions and outcome measurement (different meditation traditions, varied pranayama protocols, inconsistent HRV metrics, and mixed use of office vs ambulatory BP) complicates quantitative pooling and generalisability. Second, variable methodological rigour and reporting (small sample sizes, inadequate blinding, and incomplete description of breathing protocols) reduce confidence in effect-size estimates; these shortcomings mirror concerns raised in the HRV biofeedback and breath-training literature about inconsistent protocol reporting and resonance-frequency assessment [33,34]. Third, short follow-up in many trials limits inference about durability of effects; some meditative benefits on blood pressure appear to attenuate without sustained practice or reinforcement [32]. Fourth, adverse events and variability in individual response are under-reported: growing evidence shows that some participants experience transient unpleasant psychological or autonomic reactions to meditation or intensive breathwork, underscoring the need for systematic monitoring and reporting of harms in future trials [36–38].

Safety considerations: Although most studies report few or no serious adverse events, systematic reviews and observational work indicate that a non-trivial minority of meditators report distressing experiences (dizziness, nausea, derealization, or increases in anxiety) particularly with intensive practices or in vulnerable individuals. Clinical protocols should therefore include screening for psychiatric vulnerability, graduated training intensity, and mechanisms for clinical follow-up if adverse events occur [36–38].

Recommendations for future research: To strengthen the evidence base and enable meta-analytic synthesis, future trials should:

• Use standardised, well-described intervention protocols (specifying breathing rates, session length, and instructor qualifications) and report adherence.
• Incorporate ambulatory blood-pressure monitoring and harmonised HRV metrics to enhance clinical relevance and comparability.
• Include longer follow-up and prespecified analyses of maintenance of benefit and dose–response relationships.
• Routinely collect and report adverse events with validated instruments to characterise the incidence and predictors of harmful responses.
• Explore mechanistic end points (baroreflex sensitivity, autonomic neural imaging, inflammatory biomarkers) in nested mechanistic substudies to clarify pathways of benefit. The HRV biofeedback and resonance-breathing literature offers mature methodologies for such mechanistic assessments [29,32,33].

The evidence synthesised in this review indicates that meditation, paced-breathing and integrated yoga approaches produce complementary improvements in cardiovascular regulation and respiratory function through autonomic and mechanical pathways. While these interventions have clear promise as low-risk adjuncts to conventional care, broader adoption requires larger, rigorously designed trials with standardised protocols, longer follow-up and systematic harm surveillance to define efficacy boundaries, sustainability, and patient selection criteria.

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