Resonance breathing and postural resonance: acute autonomic and hemodynamic responses in a three-condition crossover trial

Abstract Resonance breathing (RB) and postural resonance (PR) are rhythmic interventions proposed to engage cardiovascular regulation through respiratory and postural pathways, but their acute autonomic and hemodynamic response profiles have not been directly compared. Twenty-seven healthy adults aged 18–25 years completed Control, RB, and PR in a three-condition crossover design. Control was performed first, whereas the order of RB and PR was counterbalanced, with a 5-day washout between sessions. Each session comprised a 10-min baseline, a 15-min condition period, and a 5-min recovery. Skin sympathetic nerve activity (SKNA) and heart rate variability were recorded continuously; blood pressure was assessed at baseline, immediately post-condition, and after recovery; and brachial–ankle pulse wave velocity (baPWV) was measured before and after each condition. Baseline-referenced changes during the intervention differed among conditions for mean SKNA (aSKNA), burst area, RMSSD, and R–R interval. During recovery, within-condition analyses showed lower aSKNA and burst area together with higher R–R interval and RMSSD relative to baseline after RB, whereas PR showed lower burst area relative to baseline; however, between-condition recovery changes in aSKNA, burst area, and RMSSD were not significant. PR produced greater reductions in systolic blood pressure than Control and RB both immediately post-condition and during recovery, while immediate diastolic blood pressure and mean arterial pressure responses also differed among conditions. PR also reduced bilateral baPWV within condition, and pre-to-post baPWV changes differed among conditions for both right and left baPWV. Overall, RB and PR produced distinct acute physiological response profiles, with RB characterized predominantly by autonomic modulation during recovery and PR by more pronounced acute hemodynamic responses. These findings highlight the physiological distinction between RB and PR and provide a basis for future studies examining their longer-term effects and potential clinical relevance. Trial registration : ClinicalTrials.gov, NCT07536997.