Abstract
Firefighters (FF) experience elevations in stress biomarkers during live-fire suppression, which is posited to exacerbate cardiovascular disease (CVD) risk. It is unclear if the physiological stress response differs between low-risk (LOW) and moderate-risk (MOD) FF classified by the American College of Sports Medicine (ACSM) standards. PURPOSE: This study assessed the differences in stress response to a live fire-training evolution (LFTE) between LOW and MOD CVD risk classification groups. METHODS: Forty-four (n=44) FF completed an annual clinical health assessment, wherein they were risk-stratified in LOW or MOD classifications based on the ACSM criteria. Saliva samples were collected baseline (BL), immediately post (POST), and 30-min post the LFTE and analyzed for α-amylase (AA), secretory immunoglobulin-A (SIgA), and cortisol (CORT). Data were analyzed via a general linear model (GLM) multivariate and univariate analysis. RESULTS: GLM analysis revealed an overall time effect (p<0.001, ηₚ²=0.216) with no group x time effect (p=0.796, ηₚ²=0.019) for the salivary stress biomarkers. The univariate analysis revealed no group x time effects were found for AA (p=0.481, ηₚ²=0.011), SIgA (p=0.817, ηₚ²=0.003), and CORT (p=0.511, ηₚ²=0.016; however, there were time effects for AA (p<0.001, ηₚ²=0.244), SIgA (p<0.001, ηₚ²=0.261), and CORT (p=0.003, ηₚ²=0.133). Immediately post-LFTE concentrations were significantly higher for AA (p<0.001), SIgA (p<0.001), and CORT (p=0.004) than at baseline. There was a significant group effect for AA (p=0.049, ηₚ²=0.089), with the MOD group having lower overall AA values than the LOW group, whereas there were none for CORT (p=0.427, ηₚ²=0.015) or SIgA (p=0.204, ηₚ²=0.038). CONCLUSION: These data demonstrate that the ACSM risk-stratified classifications for low and moderate CVD risk do not impact firefighting stress response. While a healthier FF is more likely to handle the demanding occupational task requirements better than their unfit counterparts, future work should elucidate the impact of stress on CVD risk and occupational performance.
Recommended Citation
Hines, Kelly; Sowinski, Ryan; Martin, Steven E.; Colvin, Lisa C.; McAllister, Matthew J.; and Gonzalez, Drew E.
(2025)
"No Impact of Cardiovascular Disease Risk Classification on The Stress Response to Firefighting,"
International Journal of Exercise Science: Conference Proceedings: Vol. 2:
Iss.
17, Article 19.
Available at:
https://digitalcommons.wku.edu/ijesab/vol2/iss17/19