Effects of voluntary slow breathing on heart rate and heart rate variability: A systematic review and a meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of 223 interventional studies
PubMed 35623448 · doi:10.1016/j.neubiorev.2022.104711
What was done
Authors conducted a systematic review and meta-analysis of studies investigating the effects of voluntary slow breathing on vagally-mediated heart rate variability (vmHRV). From 1,842 identified abstracts, 223 studies were analyzed across three timeframes: during the session (n = 172), immediately after a single session (n = 16), and after a multi-session intervention (n = 49).
What was found
Voluntary slow breathing produced increases in vmHRV across all three evaluated conditions: during the breathing session, immediately after one session, and after multi-session interventions. No specific effect sizes, confidence intervals, or numerical data were reported in the abstract.
Why it matters
This meta-analysis aggregates evidence demonstrating that slow breathing consistently stimulates parasympathetic cardiac regulation, supporting its application as a low-cost, low-risk adjunct intervention for health and stress regulation.
Limits
The abstract omits numerical effect sizes, p-values, confidence intervals, and participant totals or demographics. The specific study designs (such as randomized trials versus uncontrolled within-subject designs) comprising the 223 included studies are not detailed in the abstract.
Cited by
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