Clinical application of abdominal breathing training and evaluation of physical and mental benefits in anxiety patients

Background Anxiety disorders represent highly prevalent mental health conditions globally (lifetime prevalence: ~7–14%). Current pharmacological treatments carry risks of dependence and metabolic side effects, while psychological therapies face accessibility limitations. There is an urgent need to develop safe, accessible non-pharmacological interventions. This single-blind randomized controlled trial systematically evaluated the efficacy and sustainability of an 8-week standardized abdominal breathing training program in alleviating anxiety symptoms and modulating autonomic nervous function in patients with anxiety disorders. Methods A total of 120 outpatient participants (aged 18–65 years) meeting ICD-10 diagnostic criteria for Generalized Anxiety Disorder were recruited. Participants were randomly assigned to either an intervention group (abdominal breathing training, n = 60) or a control group (treatment-as-usual, n = 60). The intervention group received professionally supervised training consisting of 3–4 daily sessions of 10–15 min each (inhale:exhale ratio = 1:2; inhalation 3–5 s/exhalation 5–7 s). Adherence was monitored via respiratory sensors (mean adherence rate: 92.4%). Assessments using the Self-Rating Anxiety Scale (SAS) and physiological measurements—including heart rate (HR), respiratory rate (RR), blood pressure (BP), and heart rate variability (HRV-LF/HF ratio)—were conducted at baseline, post-intervention (8 weeks), and at 4-week follow-up (intervention group only). Results Anxiety symptom improvement : Two-way repeated measures ANOVA revealed a significant group × time interaction effect on SAS scores ( p < 0.05). Post-intervention, the intervention group exhibited a significant reduction in SAS scores compared to baseline (67.57 ± 8.88 vs. 71.80 ± 3.99, p < 0.001), reflecting a 5.9% decrease, and scores were significantly lower than the control group (70.43 ± 4.33, p = 0.027). At 4-week follow-up, despite a slight rebound, SAS scores in the intervention group remained significantly below baseline (68.57 ± 8.11, p < 0.05). Physiological optimization : For physiological indicators, significant group × time interaction effects were observed (all p < 0.05). Post-intervention, the intervention group showed significant reductions in heart rate (77.08 ± 10.30 vs. 83.37 ± 9.67 bpm), respiratory rate (17.37 ± 1.78 vs. 18.60 ± 1.83 breaths/min), systolic blood pressure (114.12 ± 11.97 vs. 122.63 ± 12.18 mmHg), and diastolic blood pressure (74.40 ± 6.75 vs. 80.28 ± 7.58 mmHg) (all p < 0.05). Concurrently, the HRV-LF/HF ratio increased significantly ( p = 0.008). Conclusion Standardized abdominal breathing training significantly alleviates anxiety symptoms (effect size Cohen’s d = 0.61) and induces sustained physiological improvements in autonomic regulation (effects maintained 4 weeks post-intervention). As a cost-free, non-pharmacological intervention devoid of adverse effects, it provides an effective adjunctive treatment option for anxiety disorders, particularly benefiting medically underserved populations and individuals with medication intolerance, suggesting significant clinical potential.