I have posted this article a couple of times over the past 4 years on the firerescuefitness.com blog, I think it is one of the most overlooked aspects of firefighter fitness. Its starting to get cold outside (at least here in the Midwest) and its easy to think that hydration isn’t as important as staying warm. Dehydration is still very much a threat to firefighters performance (and survival) in winter just as much as it is in summer. The combination of heavy clothing and high-intensity exercise can lead to increased sweating and the possibility of dehydration. You may not feel as thirsty in cold weather as in other climates, because your body chemistry impairs your brain’s ability to tell you when to hydrate. Cold weather also has the effect of moving body fluids from your extremities to your core, causing increased urine output and adding to dehydration. Please take note at how quickly a dehydrated fire rescue athletes’ performance can diminish.
In most stations, your shift starts with checking your gear, SCBA, med supplies and looking over the apparatus (usually with a cup of coffee in hand), but do you ask yourself, Am I physically ready to do my job? I imagine 100% of you nodded your head in affirmation to that seemingly rhetorical question.
Hydration and the Human Body
The human body is 66–70% water. Under normal circumstances, the human body loses about 35–90 oz. of water a day through body waste, sweat and breathing (Maughan, 2003). During normal athletic activity, the body can lose 8–16 oz. of water per hour. The extreme conditions of firefighting demand more than this. On average, working firefighters should anticipate losing 50–70 oz. of sweat in 30–45 minutes of fireground activity (Levine et al., 1990). For a 200-lb. firefighter, a 2% sweat-induced loss of body weight would require a post-exercise fluid intake of about 96 oz. or more, considering the individual was well hydrated before the call.
A Matter of Life and Death?
Hydration is critical for optimal performance. Progressive dehydration from exercise (or fireground operations) impairs performance, mental capacity and perception of effort, and it can be life-threatening. With as little as a 2% shortage of body water, the ability to perform a high-intensity activity can be greatly impaired (Kleiner, 1999). The combination of the hot environment and the protective gear insulating the firefighter can produce dangerous conditions of hyperthermia and dehydration.
Properly hydrated, well-conditioned firefighters are therefore much better able to contend with heat stress than their unconditioned and/or dehydrated counterparts. Put that into the context of your crew, which is only as strong as its weakest member. If you don’t hydrate yourself properly before arriving on the fireground, you’re not only putting your own life in danger, but the lives of your crewmembers as well, because your performance level could be greatly reduced (IAFF, 2006). For these reasons, dehydration must be addressed before the firefight begins.
How to Hydrate
To stop dehydration before it starts prior to the alarm for a service call, you must limit the use of stimulants, such as caffeine, avoid carbonated beverages, maintain physical fitness and stay adequately hydrated throughout a shift. Drink plenty of water at regular intervals, and aim to replace fluids at the same rate that they’re lost. At minimum, consume 64 oz. of water a day (Casa et al., 2000). Increase that amount when exercising on duty and after you’ve completed your workout to avoid being dehydrated at the scene.
Follow these recommendations, feel free to print these out and post around the firehouse. (Click here to download a printable version)
This is an insert from an article I wrote from FirefighterNation.com (you can read the entire article by clicking here). Please like and comment on the article.
Stay safe and healthy,