Background: Fencers often complain of progressive difficulty in breathing during matches, which is generally attributed to restricted air, light and heat circulation from wearing a mask. Physiologically, the nasal structure generates airflow resistance that can reach -50% of the total respiratory resistance. Objectives: This study aims to investigate the presence of nasal obstruction in fencers and the relationship with the use of mask. Materials and Methods: An observational study on 40 fencers (18 males, 22 females) was conducted. Fencers perform a usual assault, wearing the mask and standardized physical exercises (running, sprints and obstacles) without the mask. ENT examination with a nasal flexible fiberscope, Anterior Active Rhinomanometry (AAR) and Peak Nasal Inspiratory Flow (PNIF) measurement before and after physical activity with or without the mask was recorded. Results: Before physical exercise, the total nasal airway resistance mean value for AAR was 0.33 ± 0.17 Pa/cm3/s at 150 Pa. After a match with the mask, the mean value was 0.28 ± 0.16 Pa/cm3/s. After normal physical exercises without mask, the mean value was 0.24 ± 0.15 Pa/cm3/s. Using t tests, statistically significant difference between nasal resistance before and after physical activity (P < 0.05) was observed, but no significant difference in nasal resistance between the basal value and that taken after a match wearing the masks (P = 0.1265). PNIF values significantly increase with exercise (P < 0.05). Conclusions: Our study shows that wearing the mask causes increased breathing impairment in fencers, when compared with similar physical activity without the mask
