12-weeks of Slow Breathing Exercises Reduces Blood Pressure among Healthy Normotensive Subjects

Slow breathing exercises are a key component to many mind-body practices used for stress reduction and modulation of autonomic tone, and it has been shown to reduce blood pressure acutely. Long-term effects on blood pressure and autonomic tone are not well documented. We studied 95 healthy participants (41±4 years, 76% female) who performed slow breathing exercises for 12 weeks and examined the effect of slow breathing on systolic blood pressure, diastolic blood pressure, and autonomic tone. At baseline average BP was 105±11/67±8 mmHg. Among the 11 participants with elevated blood pressure, BP was 126±11.0/ 80±5 mmHg. Our comparison group, that received no intervention, consisted of 30 participants with baseline mean BP 125±19/ 71±10 mmHg. SBP and DBP decreased significantly (−2.4±7.3 and -1.6±5.5 mmHg, respectively) at 12 weeks for all participants who practiced slow breathing. The comparison group showed no significant changes in blood pressure. Blood pressure reduced further among slow breathing participants with baseline SBP over 120mmHg and/or DBP over 90mmHg (−10.3±7.9 and -3.8±5.5 mmHg, respectively). In our regression model, baseline SBP was associated with further decreases in SBP from baseline to 12 weeks. No significant changes were observed in spectral analyses from baseline to 12 weeks or correlations between spectral analyses in blood pressure. In conclusion, 12-weeks of slow breathing exercises resulted in a significant reduction of blood pressure in the absence of significant changes in autonomic tone as measured by spectral analyses. Further research into the mechanisms and effectiveness of slow breathing on cardiovascular health is needed. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial NCT02870868 ### Funding Statement This study was funded in part by grant R61-AT009340 from the NIH. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study was approved by the Vanderbilt University Institutional Review Board. Written consent was obtained from each participant and the study was registered in ClinicalTrials.gov prior to enrollment ([NCT02870868][1]). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT02870868&atom=%2Fmedrxiv%2Fearly%2F2022%2F08%2F31%2F2022.08.30.22279389.atom