To Drink Or Not To Drink - It Used To Be So Easy!
We have been urged by health-care organizations and government agencies such as "US Department of Heath and Human Services- National Institutes of Health" to reduce our sodium intake due to a possible link between high sodium intake and high blood pressure in certain individuals. Many diseases are worsened by extremely high sodium intake. I feel these guidelines are for the general population and don't apply to a small percentage of extremely physically active adults who indulge in long duration endurance events - especially in hot, humid conditions.
Unfortunately, as we all know most of us need not worry about the consequences of long duration exercising, since exercise in general is not on most people's agenda, much less exercise of any length in extreme conditions. However, we need sodium for normal bodily functioning. We can lose abundant amounts of sodium through sweat and urination during prolonged activity. This article is geared toward those of us who enjoy partaking in extended periods of exercise (measured in hours instead of minutes) and the important need to pay attention to the delicate water/sodium balance in our bodies, and the real possibility of taking in TOO MUCH WATER without adequate electrolytes and the serious consequences that may result.
After doing some preliminary research on the percentage of people this article would actually apply to, I was surprised to find out how small of niche we are, that is professional athletes, recreational swimmers, bikers, runners/hikers/walkers/climbers, triathletes, adventure racers, and military personal who enjoy testing their mental and physical limits through prolonged exercise. Sometimes overlooked, but fortunately for all of us, there are many extremely physically fit, mentally tough people in the Armed Forces, especially in the elite divisions.
It was very hard to get accurate numbers of "endurance exercisers" so I came up with my best guess based on the following criteria. The U.S Census Bureau, which runs an interactive (up to the minute) U.S POPClock Projection states the resident population of the United States (292,977,183 - when this article was written) the World POPClock Projection states the total population of the World (6,359,215,095 - also when article was written). I also found an interesting article at MarathonGuide.Com titled "USA Marathoning: 2003 Overview". The article estimates there were nearly 334,000 people who completed a marathon in the USA in 2003. I also found at SlowTwitch.Com an article titled "The State of The Sport". This article estimates that approximately 130,000 people will compete in at least one triathlon in the US (2002). According the US Department of Defense there are 1.37 million active duty forces (2001).
I realize my guess is simply that, and I don't take into account the rest of the world's large number of "hardcore" exercisers. I still come up with a very small fraction of people that should be concerned about the dangers of "water intoxication". My rough guess would be based on the very loose figures of 334,000 official marathon finishers, 130,000 triathletes, 1,370,000 military personal (of which all don't fit the profile - this probably more than makes up a portion of the several hundred thousand or more other "hardcores" I neglected to include), 100,000 or so professional/semi-professional athletes, 200,000 high school/college athletes, throw in 15,000 ultras/adventure seekers/racers divided by the total US population (292,977,183) and you come up 0.73 percent of the US population who could potentially be affected by "over-drinking". I realize this all was probably an exercise in futility, although I do have a better feel for smallness of our "family".
When I first started running in the mid-eighties the old axioms were "drink before you are thirsty", "never run past a water station during a marathon", "it is virtually impossible to over-hydrate", "your thirst is no indication of your fluid requirements", "stay ahead of your thirst - you can't catch up", and so on. These days things are much more complex. When people started dying during marathons, some of these old axioms where questioned. We have since learned that it is possible to drink too many fluids. Most people affected by "water intoxication" were middle to back of the pack runners finishing a marathon in four hours or more.
Hyponatremia (HYPE-O-NAY-TREEM-EE-A) is the culprit. Basically, it is a condition that results in an abnormally low concentration of sodium levels in the bloodstream. Low levels of sodium can cause cell malfunction, and in extreme cases can be fatal due to swelling of the brain. Being that I am just a layman I can give you a very simplistic explanation from what I understand about the causes of hyponatremia. When we sweat we lose water and salt through perspiration. By ingesting large amounts of plain water without additional salt we dilute the sodium levels in our bloodstream. This is not a problem in the short term, but as time goes on, especially in extreme heat, the delicate balance between the body's water/sodium levels can create real problems. The problem can also occur during cool weather if you take in too much plain water without additional salt.
Very few commercially available sports drinks contain enough sodium to replenish lost reserves of sodium during long duration events such as a marathon or an Ironman. Studies have shown it is possible to lose as much as two grams of sodium per hour. You may need to eat sodium rich foods or use salt supplements to replace the sodium depletion. While everyone is different a general recommendation seems to be you should be ingesting one gram of sodium per hour during a long event. One gram of sodium is 2.5 grams of table salt and one tablespoon weighs 6.6 grams, so you would need less than half a tablespoon per hour. People under a doctor's care or who already have an underlying medical condition should consult their health care provider about salt and their ability to exercise for extended periods of time, especially in the heat.
Classic hyponatremia symptoms can range from mild to severe and can include - nausea, a feeling of fullness or bloating in your stomach, vomiting, headaches, bloating/puffiness in the face, fingers, wrists or ankles, muscle cramps/weakness, slurred speech and disorientation/confusion. Unfortunately these symptoms are similar to dehydration, which causes the person to think they need to drink more, exacerbating the problem. If symptoms progress, victims may experience seizures or lapse into coma, and death may even occur.
Lately there seems to be a rise in the number of reported cases and tragically even some deaths linked to hyponatremia. Runners have died in recent years at the Boston, Marine Corps and Chicago marathons. Please see the articles linked from RememberCynthia.Com, a wonderfully heartfelt Web site designed by the sister of Cynthia Lucero who died as a result of hyponatremia at the Boston Marathon - "How Marathons Can Kill You" from The Chicago Sun Times and from the The Boston Globe - "In The Long Run, Marathon May Hurt" and "Marathon Runner's Death Linked to Excessive Fluid Intake".
This rise in reported cases could be due to the renewed popularity of the marathon and the fact that a large majority of participants are fairly new or novice runners, many of them running as "charity runners". I know the trouble you can get into when you generalize, but here goes; Generally speaking many of these new runners are less conditioned and slower than more experienced runners. They are also less in touch with their bodies, their individual hydration needs and the stresses of long term exercise, with many having finish times well over four hours. That coupled with the old adages about the danger of dehydration, causes newcomers to be almost fanatical about their fluid intake without the consideration of additional sodium.
This condition seems to affect more women than men. There are several theories as to why, including smaller body size, hormonal shifts more varied than males, being more apt to pay attention to their water intake than males, and possibly more likely to listen to advice from coaches and fellow runners about the dangers of dehydration.
I think it is important to mention that dehydration is a very real problem in and of itself. Please see the article "Fluid Replacement: The American College of Sports Medicine Position Stand" at Gatorade Sports Science Institute Web site. There are several other articles of interest at this Web site - "The Risk and Reality of Hyponatremia" and "Hyponatremia In Athletes". I think you need to educate yourself through reading and of course through training as to reaching a happy medium between not drinking enough and drinking too much. However, I do think not enough people are aware of the dangers of drinking too many fluids.
What qualifications or credentials do I have to be dispensing information about a potential life threatening condition? That is a fair question. Actually I have absolutely none - no, nada, zero, zilch training in this area. I don't have any medical training whatsoever, although I have done a fair amount of reading on this subject and I do have considerable real world "endurance event" experience. I don't profess to be an authority of any kind on this issue. I fully realize the seriousness of "water intoxication" and how this condition can be fatal. I am not giving advice, just my opinions and what I feel to be a well-rounded source of articles. That is why I link you to "THE EXPERTS" in the field and let you decide what you take from the information.
I did have had a very small taste of the debilitating effects of hypontremia during the 2003 Ironman Wisconsin. At the time I don't really think I was fully aware of why I was feeling so totally wiped out. I had a slight feeling of disorientation, a minor headache, and my stomach was sloshing around like waves on the ocean, yet I was still thirsty. It was an extremely warm, humid day and I did not pay attention to the enormous amount of water I was drinking - without the proper addition of salt. Fortunately, I completed the event and had no lasting problems. I had finished four Ironman's along with many marathons previously and never even thought it was possible for me to drink too much. After that experience I begin reading as many articles as I could find on the subject of hyponatremia.
After doing some research and poring over many articles and Web sites, I decided to try a product from E-Caps.Com called Endurolytes. I have been using this electrolyte replacement product on my long runs (anything over two hours) and during several recent marathons. I have not noticed any ill effects and seem to feel much more comfortable during the later stages of a long session. I plan to continue with this product and use it during the summer and the 2004 Ironman Wisconsin.
Please see the article "USATF Announces Major Change In Hydration Guidelines", dated April 2003, posted on the USA Track & Field Web site. They are the national governing body for track & field, long-distance running, and race walking. There are new parameters regarding hydration due to the new understanding involving fluid intake and distance events, such as marathons, triathlons, and other ultra-distance endeavors. The USATF have posted several other very interesting and informative articles on their site on the subject of hydration. Another very good article, "IMMDA Advisory Statement On Guidelines For Fluid Replacement During Marathon Running" goes into detail on the changing of prevailing attitudes on hydration and provides some interesting historical details on marathons and their evolution. The article "Proper Hydration for Distance Running - Identifying Individual Fluid Needs" is very useful in understanding the difference between dehydration (the ingesting of too few fluids) and over hydrating (hyponatremia) and avoiding both scenarios. Unfortunately, as I stated previously it seems to me that both conditions have very similar symptoms. The article "Fluids On Race Day" brings out some important points on running and ingesting pain relievers.
Everyone's fluid needs are a little bit different and there are no hard and fast rules. However, there are guidelines that apply to most people. The article "Self-Testing Program for Optimal Hydration" at USA Track & Field and teaches you how to figure out your own individual optimum water intake per hour can be very useful. I personally feel that the above-mentioned articles are a "must read" for someone who plans on physical endeavors lasting longer than several hours.
And remember we all have a great Research & Development Laboratory literally right at our fingertips - our body, uniquely our own. Use your training time as a playground to introduce new toys, fuels, fluids, and techniques. Events and races should just be quickened extensions of proven, repetitive, time-tested workouts done without throwing your body any curves when you are counting on "firing on all cylinders". Save the R&D for the playground.
Since you are not paying to read this and I am certainly not being paid to write it, may I go out on a tangent? I think the real benefit of ultra endurance events is introspective, in other words a personal development tool. Finishing these insane, crazy distances makes us no better person than the next. For example, few people even know what an Ironman consists of, or the distance of a marathon, and most don't even care to know. Although, by competing in them, I believe we finish mentally so much further ahead than before we started. These events make us so much better than our "pre-race" days.
I don't think you can truly appreciate these endurance events until you personally experience how humbling, physically and mentally, they can be. In some ways I guess I am saying you can't really respect the race until the race has beaten you, or at the very least you have beaten the race by just one single step. The "race" will always be there waiting patiently for your next attempt.
The quote by 19th century German philosopher Friedrich Nietzsche, - "That which does not kill us makes us stronger", is open to many interpretations. I certainly have no idea, but I doubt he was referring to endurance exercise in that particular quote. I have found my own interpretation of that quote in that in some way by competing in these events, I seem to develop an inner strength that carries over to handle everyday life's calamities more calmly. And most importantly this short term self-induced suffering makes me more sympathetic to those whose life is a constant cycle of suffering, bringing me to realize how good my life actually is. Also, this brief, temporary self-induced suffering gives an exit from the material world and makes me realize that when it comes down to it, we are all the same - my pain is no greater or more important than anyone one else's. Lastly, it feels so dog gone good to stop!
I certainly don't expect anyone else to understand this drivel. Since, I guess the same end result could be accomplished by beating my head against a concrete wall and then stopping. However, to abuse another quote, this one from Joseph Dunningert, the famous magician/mentalist (April 28,1892 - March 9, 1975) - "For those who believe, no explanation is necessary. For those who do not, none will suffice." Again, I doubt that this quote was referring to endurance events although my out of context take on this quote is, that if you don't partake in these events you will never understand why people do compete in them.
I don't profess to be an authority of any kind on these issues or have any special insight. And I make no claims to being anything other than an infant in the ultra endurance world. I do know there is always more to learn and I make a point of always keeping an open mind to trying new things.
I would like people to realize that when we sign our name beneath the waiver's fine print, which by the way seems to get "finer" every passing year, that there are inherent risks associated with long duration exercise and to read as much related current information as you can because the information you thought was gospel yesterday may no longer be accurate today.
©Copyright 2003 - 2015 Stephen Vincent LLC. All rights reserved®.