{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T04:30:43Z","timestamp":1786595443428,"version":"build-2736575974"},"reference-count":44,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T00:00:00Z","timestamp":1786579200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Netw. Physiol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Combat-related stress is associated with autonomic nervous system (ANS) dysregulation\u2014sympathetic predominance, reduced vagal tone, and decreased heart rate variability (HRV)\u2014linked to increased cardiovascular risk. Non-pharmacological interventions targeting autonomic regulation show promise, but controlled studies in combat-exposed populations remain limited. We assessed whether adding a structured breathing\u2013meditation protocol, the Technique of Mental Relaxation (TMR), to standard rehabilitation is associated with changes in HRV and electrocardiogram (ECG)-derived indices of autonomic regulation in Ukrainian servicemen.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A controlled, non-randomized study screened 84 male servicemen; 77 were allocated to a TMR group (n = 37; TMR plus standard treatment) or a control group (n = 40; standard treatment alone). Paired baseline and post-treatment 5-min supine recordings, obtained over a 14-day rehabilitation period, were available for 74 participants (TMR n = 35, control n = 39); a civilian reference group (n = 89) provided baseline comparison. Primary HRV outcomes were SDNN, RMSSD, the Baevsky Stress Index, and heart rate; ECG analysis added repolarization intervals, with Hedges\u2019 g.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>At baseline, both military groups showed impaired autonomic regulation versus civilians (all p &amp;lt; 0.0001). After intervention, the TMR group improved (SDNN 23\u219230 ms, p &amp;lt; 0.001; RMSSD 12\u219219 ms, p &amp;lt; 0.001; Stress Index 422\u2192253, p &amp;lt; 0.001), whereas controls deteriorated; post-treatment between-group differences were significant for all primary outcomes (p \u2264 0.008).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Heart-rate-adjusted analyses attenuated part of this difference, the Stress Index remaining most robust. Given the non-randomized design, these findings warrant caution and support randomized trials, with HRV as an objective monitoring tool.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fnetp.2026.1912231","type":"journal-article","created":{"date-parts":[[2026,8,13]],"date-time":"2026-08-13T04:24:15Z","timestamp":1786595055000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Heart rate variability, ECG minor changes, and HRV\u2013ECG coupling associated with an adjunctive structured breathing\u2013meditation protocol in combat-exposed military personnel"],"prefix":"10.3389","volume":"6","author":[{"given":"Viktor S.","family":"Matsyshyn","sequence":"first","affiliation":[{"name":"State Administrative Department, State Institution of Science \u201cCenter of Innovative Healthcare Technologies\u201d","place":["Kyiv, Ukraine"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anatolii M.","family":"Kravchenko","sequence":"additional","affiliation":[{"name":"State Administrative Department, State Institution of Science \u201cCenter of Innovative Healthcare Technologies\u201d","place":["Kyiv, Ukraine"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nataliia M.","family":"Ovodiuk","sequence":"additional","affiliation":[{"name":"State Administrative Department, State Institution of Science \u201cCenter of Innovative Healthcare Technologies\u201d","place":["Kyiv, Ukraine"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dmytro Y.","family":"Zharkov","sequence":"additional","affiliation":[{"name":"Department of Contactless Control Systems, V.M. 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