Effects of Nasal Breathing Exercise on Systemic and Cellular Inflammatory Biomarkers

Effective inflammatory control is required to maintain proper immune function and health. While nasal breathing (NB) is recognized for its respiratory and cognitive benefits, its influence on immune regulation remains unclear. PURPOSE: The current study examined the effects of acute and chronic NB exercise on pro- and anti-inflammatory cytokines in serum and peripheral blood mononuclear cells (PBMCs). METHODS: Twenty-two sedentary men (age=21.55±2.58 years, height=180.98±7.89 cm, and weight=86.81±14.33 kg) were randomly assigned to either the NB (N=11) or combined breathing group (CB, N=11). Participants performed aerobic exercise on a recumbent cycle at a moderate intensity (70% VO2max) for 4 days/week over 4 weeks. Blood samples were collected pre- and immediately post-exercise (IPE) to assess changes in inflammatory cytokines before and after a 4-week exercise intervention. PBMCs were isolated by density-gradient centrifugation with Lymphoprep, and concentrations of cytokines (IL-10, TNF-α, and IL-6) were compared between serum and PBMCs. RESULTS: Serum IL-10 levels (33.63±20.69 pg/mL) were significantly higher than PBMCs (7.76±5.20 pg/mL, p=0.001), whereas there were no significant differences in TNF-α (7.64±1.29 vs. 7.10±0.51 pg/mL, p=0.073) and IL-6 (2.37±0.12 pg/mL vs. 2.36±0.08 pg/mL, p=0.849) between serum and PBMCs, respectively. Interestingly, serum TNF-α, not IL-6 or IL-10, was significantly (p=0.045) lower in the NB group (7.15±0.47 pg/mL) than the CB group (8.13±1.67 pg/mL). PBMC cytokines, however, showed no changes following the 4-week exercise intervention, either within or between groups. CONCLUSION: This study provides preliminary evidence that nasal breathing exercise may modestly modulate systemic inflammatory responses. While a short-term NB exercise training did not elicit significant changes in cytokine concentrations, the lower serum TNF-α suggests a potential anti-inflammatory effect. The absence of significant changes in IL-6 and IL-10, both serum and PBMCs, may be due to the relatively short exercise duration and moderate exercise intensity. These results indicate that respiratory patterns during exercise may influence inflammatory regulation, warranting further research into longer interventions and mechanisms involved.