Eur J Sport Sci. 2026 Aug;26(8):e70227. doi: 10.1002/ejsc.70227.
ABSTRACT
The effects of exercise intensity on airway epithelial integrity markers and inflammatory responses remain unknown. Therefore, we investigated the effects of high- and moderate-intensity exercise on airway epithelial integrity markers (club cell protein 16 [CC16], surfactant protein D [SP-D], and the CC16/SP-D ratio), along with systemic inflammation assessed via high-sensitivity C-reactive protein [hs-CRP] in healthy young men. Twenty healthy young men were randomly divided into two groups: high-intensity (n = 10) and moderate-intensity (n = 10) and both groups completed 20-min of continuous intensity treadmill exercise. The exercise intensities for the high-intensity and moderate-intensity groups were 85%-90% and 65%-70% of maximum heart rate, respectively. Serum was collected before and at +1 and + 24 h after exercise. CC16, SP-D, and hs-CRP concentrations were measured using enzyme-linked immunosorbent assay. A two-way repeated measures analysis of variance suggested that CC16, SP-D, CC16/SP-D ratio, and hs-CRP changed significantly over time (p < 0.05). Time × group interaction effects were observed for CC16 (p = 0.032) and CC16/SP-D ratio (p = 0.010) but not for SP-D (p = 0.824) and hs-CRP (p = 0.422) concentrations. Post hoc analysis revealed that CC16 concentrations at +1 h (p = 0.002) and the CC16/SP-D ratio at +24 h (p = 0.005) were higher for the high- compared to the moderate-intensity group. Our findings suggest for the first time that exercise intensity has a significant impact on CC16 and the CC16/SP-D ratio but does not affect the release of SP-D or hs-CRP.
PMID:42489020 | DOI:10.1002/ejsc.70227
