In addition to these benefits, exercise also strengthens the heart muscle, enhances the blood dissolving capacity of the blood — making unwanted clots less likely — and stabilizes the electrical activity of the heart.
The not so obvious benefits are important to anyone that has a job that demands immediate response and repeat response. Active firefighting is a tremendously strenuous task. The firefighter can be taken from a complete resting state and within minutes be thrust into a dangerous, complicated environment where he or she is expected to perform at a demanding physical level. Firefighters face a potentially deadly combination of stress, heat and high body temperature and dehydration.
Dr. Stefanos Kales, MD, a Harvard researcher, led a study that analyzed data on all firefighter deaths between 1994 and 2004, except those linked to the 9/11 terrorist attacks.
According to Dr. Kales, “We found that firefighters were generally very fit going into the service but over the course of a number of years — because of not exercising regularly, not eating right — many are becoming obese.”
An article in the Journal of the American Dietetic Association indicates that many overweight or obese firefighters may not even realize the potential problem.
Physical conditioning is crucial in public safety jobs because physical and emotional stress is unavoidable. Repeatedly placing such stresses upon an individual can take its toll. In stressful situations such as a fire, researchers note that the body responds with a number of physiological changes. More adrenaline is released into the bloodstream, muscles tense, breathing quickens, and heart rate and blood pressure rise. Researchers also note, however, that fit individuals tend to take these physical responses in stride and with less wear and tear to the body.
Exercise and Stress
Psychological stress has been proposed as a major contributor to the progression of cardiovascular disease (CVD). Acute mental stress can activate the sympathetic-adrenal-medullary (SAM) axis, eliciting the release of catecholamines (NE and EPI) resulting in the elevation of heart rate (HR) and blood pressure (BP). Combined stress (psychological and physical) can exacerbate these cardiovascular responses, which may partially contribute to the elevated risk of CVD and increased proportionate mortality risks experienced by some occupations such as firefighting. Studies have supported the benefits of physical activity on physiological and psychological health, including the cardiovascular response to acute stress. Aerobically trained individuals compared to unfit exhibit lower sympathetic nervous system (e.g., HR) response as shown in the chart below. This is due to enhanced cardiovascular efficiency in response to physical and/or psychological stress.
Faster Recovery and Rehab
During an event, the goal of rehab is to get the firefighter either back into action or back to the station in a safe and healthy condition. Cardiorespiratory fitness plays a huge factor in how quickly a firefighter recovers. Note that the graph on this page shows how the fit individual has a quicker recovery. Data has demonstrated the ability of physically fit trained individuals to improve adaptations to stress, including a more rapid return of HR to baseline levels.
Can you imagine military personnel — especially soldiers or marines — preparing for their jobs without fitness? Can you imagine professional and collegiate athletes preparing for a season or game without conditioning? Would you expect our Olympic athletes to enter the games without regular fitness development? Then why would you choose not to be fit in a job that demands you be prepared at the sound of an alarm?
Karen Leatherman is president/owner of Fitness Forum Occupational Testing Services. She started the first hospital-based fitness center in South Carolina where she started cardiac and pulmonary rehab programs. She has over 30 years performing exercise stress testing and has been testing firefighters for over 20 years. In addition, she was on the American College of Sports Medicine (ACSM), Health and Fitness Certification Committee where she travelled with a team from the U.S. to India and Hong Kong to teach and administer ACSM exams.