Abstract
Background: Nasal obstruction is an annoying condition. In this study, we evaluated the effects of hot spring bathing at 41 to 42°C using a rhinomanometer.
Methods: Ten healthy adult volunteers (10 men, mean age of 27.8±4.4 years) were asked to bathe in a hot spring for 10 minutes. Using a rhinomanometer (HI-801), nasal resistance was measured before and after bathing by active anterior rhinomanometry. Total nasal resistance was calculated using Ohm’s law formula with right and left nasal resistance values (1/T=1/R+1/L, T: bilateral resistance, R: right resistance, L: left resistance). Resistance at ΔP=100 Pa was used for evaluation.
Results: Right and left nasal resistance values were significantly decreased after bathing in subjects with a pre-bathing nasal resistance of greater than 0.75 Pa/cm3/s (inspiratory, P=0.0117; expiratory, P=0.0277; Wilcoxon t-test). No significant change was observed in subjects with a pre-bathing nasal resistance of below 0.75 Pa/cm3/s.Post-bathing total nasal resistance was significantly decreased in subjects with a pre-bathing nasal resistance of greater than 0.5 Pa/cm3/s (P=0.0115; Wilcoxon t-test).
Conclusion: This study showed that nasal obstruction can be improved by hot spring bathing, which may contribute to the reasons why cold symptoms are relieved by hot spring bathing.