Our study indicated that forest bathing showed the following benefits for male subjects at risk of developing COPD: (1) reductions in levels of blood CRP, IL-6, α1-AT, and fibrinogen; (2) improvement in SpO2; (3) improvement in respiratory symptoms related to COPD; (4) improvement in subjective sleep quality assessed by the OSA-MA; (5) decreased negative mood and increased positive feeling of vigor in the POMS test; and (6) improvement in subjective mental and physical fatigue symptoms. Here, SERPINA1 is linked to chronic obstructive pulmonary disease.