Firefighting causes stiff arteries and “cardiac fatigue,” conditions also found in weightlifters and endurance athletes, according to two recent studies by researchers at the Illinois Fire Service Institute, as reported by the University of Illinois news Web site.
The researchers found that three hours of firefighting activity caused acute increases in arterial stiffness and impaired cardiac functioning in young, apparently healthy male firefighters. The study, which was published recently in the journal Vascular Medicine, is believed to be the first study to examine arterial stiffness and blood flow after fire-suppression activities. “These changes appear to be similar to what is observed after maximal aerobic and/or heavy resistance exercise and are likely due to a combination of thermal, metabolic, and psychological stresses that occur during fire-suppression activities,” wrote study authors Gavin Horn, the director of research at IFSI, and Bo Fernhall, a professor in the department of kinesiology and community health in the U. of I. College of Applied Health Sciences.
The 69 firefighters who participated in the study were in active service and had been medically cleared by their home departments to participate in live-fire activities, although many were overweight, as assessed by body mass index. The participants, all male, ranged in age from 19-48, with an average age of 29.
Wearing full firefighting gear, the participants engaged in typical fire suppression activities – advancing hose, forcing doors open, extinguishing a fire – at IFSI’s training facility. They engaged in four or five activity periods, which lasted 15-25 minutes each, with several 10-15 minute rest periods in between to hydrate and cool themselves.
Shortly before and afterward, researchers measured various cardiovascular functions, including heart rate; brachial, carotid and aortic blood pressures; blood flow in their forearms; and arterial stiffness and thickness. Firefighters’ body temperatures were measured using a monitor and a small disposable sensor capsule that they ingested the night before the test.
About one hour before the pre-firefighting data collection, the participants consumed a standardized meal and a 2-gram Vitamin C capsule or a placebo so researchers could investigate whether the supplement improved arterial function, mitigating the risk of cardiovascular events, as prior studies suggested. The Vitamin C supplements did not appear to affect any of the outcomes, however.
Read more about the research HERE.