ARTERIAL STIFFNESS RESPONSES TO A SHORT DURATION, HIGH-INTENSITY SIMULATED FIRE ATTACK IN MALE CAREER FIREFIGHTERS
Tom Nagel1, Bridget Melton1, Wesley T. Blumenburg2, Brett L. Cross2, Greg J. Grosicki2. 1Georgia Southern University, Statesboro, GA. 2Georgia Southern University, Savannah, GA.
BACKGROUND: Cardiovascular events are the leading cause of death in firefighters, and nearly two-thirds of these deaths occur during or immediately following a fire suppression event. Arterial stiffness is an independent predictor of cardiovascular-specific and all-cause mortality that may be increased by a fire attack. PURPOSE: To characterize changes in central arterial stiffness, indexed as carotid-femoral pulse wave velocity (cf-PWV), and peripheral arterial stiffness, indexed as Augmentation Index (AIx), following a simulated fire attack. METHODS: Twenty-one male career firefighters (35±8 yrs; 31±5 kg/m2) reported to the testing facility in a fasted state during morning hours. After 10 minutes of supine rest, blood pressure was assessed via a brachial cuff and AIx and cf-PWV were determined via pulse waveform analysis and carotid applanation tonometry, respectively. Firefighters then participated in a seven-station simulated fire attack for time, and heart rate was continuously monitored via wireless telemetry. Brachial blood pressure, AIx, and cf-PWV were reacquired immediately upon completion. Paired t-tests were used to compare pre-post changes in blood pressure and arterial stiffness indices, and Pearson’s correlations were used to explore predictors of arterial stiffness responses. RESULTS: Average heart rate during the simulated fire attack was 164±13 bpm, and average time to completion, a surrogate for fitness, was 8.7±1.7 min. Despite significant increases (p<0.01) in mean arterial pressure (94±9 vs. 115±10 mmHG) following the simulated fire attack, cf-PWV (7.6±1.0 vs. 7.8±0.9 m/s; p=0.34) and AIx (13.8±8.6 vs. 13.9±12.3 %; p=0.98) were unaltered. Pearson’s correlations demonstrated that fire attack completion time was inversely associated with changes in cf-PWV (r=-0.53, p=0.01) but not AIx (r=-0.13, p=0.56). CONCLUSIONS: No changes in central or peripheral indices of arterial stiffness were observed following a short-duration, high-intensity simulated fire attack in male career firefighters. The observed association between fitness, indexed as fire attack completion time, and changes in cf-PWV may be explained by intensity-dependent arterial stiffness responses, whereby increases in arterial stiffness in fitter firefighters may be attributed to an ability to perform the task at a greater relative intensity.
Nagel, T; Melton, B; Blumenburg, WT; Cross, BL; and Grosicki, GJ
"ARTERIAL STIFFNESS RESPONSES TO A SHORT DURATION, HIGH-INTENSITY SIMULATED FIRE ATTACK IN MALE CAREER FIREFIGHTERS,"
International Journal of Exercise Science: Conference Proceedings: Vol. 16:
1, Article 67.
Available at: https://digitalcommons.wku.edu/ijesab/vol16/iss1/67