H₂O₂ and NO₂^- in Exhaled Breath Condensate Increase After a Wheelchair Rugby Match in Paralympic Athletes: A Possible...

Spinal cord injury (SCI) is associated with respiratory dysfunction, chronic inflammation, and oxidative stress, and can increase pulmonary tissue stress during exercise. Thus, hydrogen peroxide (H₂O₂) and nitrite (NO₂^-) concentrations in exhaled breath condensate (EBC) were compared during an official wheelchair rugby match. 14 males and two females with SCI (33.3 ± 6.5 years), anthropometry, baseline spirometry, and the International Wheelchair Rugby Federation classification (IWRF) were recorded. Playing time (23.6 ± 7.49 min), Borg scale (4.3 ± 1.64), and [H₂O₂] EBC and [NO₂^-] EBC were determined before and 20 min after the match. In the total sample, [H₂O₂] EBC and [NO₂^-] EBC increased post-match (p = 0.0042 and p = 0.031, respectively). When segmented according to IWRF classification, the highest functional capacity, H group (>1.5 points; n = 11) increased its [H₂O₂] EBC per exercise (p = 0.0029) and showed a trend for [NO₂^-] EBC (p = 0.09), while the lowest classification, L group (≤1.5 points; n = 5) showed a higher baseline concentration in both EBC markers with no changes per exercise. Baseline IWRF classification was inversely correlated with [H₂O₂] EBC, while body mass index (BMI) was positively associated with [NO₂^-] EBC. In conclusion, in the sample analyzed, a short period of moderate intensity during a wheelchair rugby match increases H₂O₂ and NO₂^- in the airway with a potentially greater effect in SCI athletes with better functional capacity; it remains to be determined whether this phenomenon corresponds to a physiological or pathological process.