The estimable British Medical Journal has just published a provocative expose on the "sports drink" industry. You know the stuff: Powerade, Gatorade, etc. As you're watching the Olympics, no doubt you've caught some screen shots of competitors drinking them and have seen their ads.
The theory behind these products is deceptively simple: Dehydration leads to decreased athletic performance. Salts are lost along with water during exercise. Exercise requires caloric expenditure. Voila! Along come products with a perfect balance of water, salt, and carbohydrate. The products come with an impressive resume of "clinical trials" attesting to their benefit, and are endorsed by a number of athletic organizations.
At first, I wasn't sure that this expose would be of interest to the wilderness traveller. As a little experiment, however, I checked out "sports drinks" and "electrolyte drinks" on a few of my favorite on-line retailers of backpacking gear: Campmor, EMS, and REI. All offer a wide variety of powdered and tablet forms of these for the camper. EMS, for example, features "GU Electrolyte Brew". The EMS website claims that the product will "get your system back in balance" and "help you go longer". Hum...
I urge you to read this report yourself. It is in the July 18, 2012 issue of the BMJ, which should be available in many university libraries. Online access is available at:
http://www.bmj.com/content/345/bmj.e4737.pdf%2Bhtml
The quick summary of the report is not pretty. The real science behind these drinks is almost completely lacking. Company claims to the contrary, when the medical journal attempted to review these studies it found virtually none of sufficient methodologic rigor to withstand scrutiny. The few which had been published in journals were overwhelmingly published in very low-impact journals with clear ties to the sports drink industry. For example, the journal Medicine and Science in Sports and Exercise is published by an organization with long-standing financial relationships to Gatorade, and has a number of "Gatorade affiliated scientists" on its editorial board.
The promoters of these products have largely "invented" dehydration as a common problem in endurance exercise, and have encouraged the promulgation of completely unsubstantiated recommendations for overhydration during sports. Unfortunately, these are filtering down to youth sports.
Is there a problem with all this? There is.
First of all, sports drinks contain calories--hundreds per serving. This may not be a problem for truly active folks, but the average person drinking Gatorade isn't Usein Bolt! By marketing an image of health and vigorous exercise, companies fool the average (mostly sedentary) user into thinking that he is drinking something other than, essentially, sugar water with a dash of salt.
More importantly, however, the widespread emphasis on sports hydration over the past few years is likely fueling a real problem: hyponatremia. This condition, which is basically a fancy name for water intoxication, is a serious cause of death and disability in some endurance sports. There are at least 16 recorded deaths and over a thousand critical illnesses in marathon running alone attributable to hyponatremia. Although sports drink makers insist that the salt content of their beverages avoids this complication, this is not correct. Indeed, an actual scientific study of marathon runners has shown that the volume of liquid consumed, independent of its composition, is the major factor in causing hyponatremia.
Millions of years of evolution have led to our bodies having an excellent mechanism for preventing dehydration. The mechanism is "thirst". Pay attention to it. When it calls, have a drink. Of water. Right from the stream!
Tuesday, August 7, 2012
Wednesday, May 23, 2012
Just when I thought I'd heard everything....
The things folks do in the backcountry never cease to amaze me. Check out this recent item from the Albany Times Union regarding some guys who became lost recently in the Adirondacks:
http://m.timesunion.com/tu/db_109215/contentdetail.htm?contentguid=QCPcA8PG&full=true#display
Peeing on each other to stay warm? Yikees!
Of course, equally important to keeping warm is keeping dry. This was obviously a counterproductive strategy. Since their names were used in the article, I suspect that most of their friends have come across this news item. At least they survived.
This brings to mind an occasional question about hypothermia--is it better to hold onto urine because it is warm, or empty your bladder? (Urinating on another camper is not usually one of the choices.) The correct answer is that it makes no meaningful difference. Urine is only warm because the body keeps it heated, so in theory less heat would expended if there were less urine in the bladder to heat. In the big scheme of things, however, the impact of this on total heat balance would be trivial. More importantly, most people with serious hypothermia are somewhat dehydrated, so the most important thing is to be drinking enough that it isn't possible to hold it!
Just don't pee on your friends.
http://m.timesunion.com/tu/db_109215/contentdetail.htm?contentguid=QCPcA8PG&full=true#display
Peeing on each other to stay warm? Yikees!
Of course, equally important to keeping warm is keeping dry. This was obviously a counterproductive strategy. Since their names were used in the article, I suspect that most of their friends have come across this news item. At least they survived.
This brings to mind an occasional question about hypothermia--is it better to hold onto urine because it is warm, or empty your bladder? (Urinating on another camper is not usually one of the choices.) The correct answer is that it makes no meaningful difference. Urine is only warm because the body keeps it heated, so in theory less heat would expended if there were less urine in the bladder to heat. In the big scheme of things, however, the impact of this on total heat balance would be trivial. More importantly, most people with serious hypothermia are somewhat dehydrated, so the most important thing is to be drinking enough that it isn't possible to hold it!
Just don't pee on your friends.
Monday, April 9, 2012
The "Trans Adirondack" Route
Erik Schlimmer is a good friend with whom I have guided in Alaska previously. He is one of the few people who approach me in the volume of untreated Adirondack water he has consumed without ill effects!
Erik has a number of "firsts" under his wilderness belt, most of which I would have no desire to duplicate. (Canoeing the lower Hudson? Yuck!) His most recent, however, looks like a lot of fun. He has outlined a 235 mile route which traverses the Adirondack Park. He will be releasing a guidebook early next year (Blue Line to Blue Line) which details the route.
This summer, Erik is working with one of his former students to produce a documentary which will coincide with the launch of his book. Information on the route and the planned documentary is available at:
http://www.kickstarter.com/projects/1559964226/trans-adirondack-route-documentary
Erik has a number of "firsts" under his wilderness belt, most of which I would have no desire to duplicate. (Canoeing the lower Hudson? Yuck!) His most recent, however, looks like a lot of fun. He has outlined a 235 mile route which traverses the Adirondack Park. He will be releasing a guidebook early next year (Blue Line to Blue Line) which details the route.
This summer, Erik is working with one of his former students to produce a documentary which will coincide with the launch of his book. Information on the route and the planned documentary is available at:
http://www.kickstarter.com/projects/1559964226/trans-adirondack-route-documentary
Saturday, March 17, 2012
Survival Lesson
For many of our frontcountry friends, outdoor education somehow equates with survival training. Such staples of television as "Man vs Wild" and "Survivorman" certainly add to this view. I had a personal taste of this a while ago when interviewed for a newspaper profile (http://adirondoc.com/publications/profile_post_061209.pdf). Not being a fan of the Discovery Channel (We only pay for basic cable.), I had a difficult time believing the reporter's questions about the utility of eating bugs and drinking urine as a survival skill. Apparently, such tripe is regular fare on such programs.
I was thinking about this the other day while reading about the seemingly amazing story of a 41 year old woman surviving a 3 1/2 week "ordeal" in the mountains of New Mexico (http://www.columbiatribune.com/news/2012/mar/10/missing-woman-survives-weeks-lost-in-nm-forest/).
No food--no water purification devices--no map or compass--below-freezing nights--her destination unknown to friends or family: this seemed like an obvious set up for fatality.
How did she survive?
Although the data are sketchy, it seems that she pretty much ignored common teaching about survival in such situations.
First of all, she drank plenty of water from a nearby creek, without fretting about its quality. While this might seem pretty basic, compare it to the arguably better-prepared chap I discussed in an earlier posting (April 27, 2010), who nearly died after a shorter period being lost because he avoided drinking for fear of water-borne illness.
Then, there is the matter of food. We often hear that the body cannot survive longer than ten days without food. This has led to the nonsense of courses on "edible plants", trapping small animals, eating bugs, etc. No one seems to realize that the energy expended by such efforts likely exceeds the minimal caloric content of the "food". Actually, the body's tolerance of extended fasting is well documented--time in excess of 40 days has been shown for centuries. Indeed, mammalian physiology is well adapted for extended periods without eating. (This is the reason that calorie restriction alone is rarely sufficient for extended weight loss.) The woman in question wasted no time or energy in pursuit of food.
She also stayed put. Although conventional teaching might have called for her to follow the nearby creek downstream, she chose not to do so. (Apparently, the unfortunate woman had some emotional disorder which contributed to her predicament, so this may not have been an informed "choice".) Rather than wasting energy and risking injury by walking distances, she simply stayed put, stayed warm, stayed dry, and waited. There are not too many areas in the US where a lost person cannot ultimately be found if she waits long enough--especially after abandoning a car.
Sure, she made some mistakes (albeit possibly intentional) which led to her near-miss. Nonetheless, we should remember the lesson of Margaret Page before pontificating on wilderness survival to our students.
I was thinking about this the other day while reading about the seemingly amazing story of a 41 year old woman surviving a 3 1/2 week "ordeal" in the mountains of New Mexico (http://www.columbiatribune.com/news/2012/mar/10/missing-woman-survives-weeks-lost-in-nm-forest/).
No food--no water purification devices--no map or compass--below-freezing nights--her destination unknown to friends or family: this seemed like an obvious set up for fatality.
How did she survive?
Although the data are sketchy, it seems that she pretty much ignored common teaching about survival in such situations.
First of all, she drank plenty of water from a nearby creek, without fretting about its quality. While this might seem pretty basic, compare it to the arguably better-prepared chap I discussed in an earlier posting (April 27, 2010), who nearly died after a shorter period being lost because he avoided drinking for fear of water-borne illness.
Then, there is the matter of food. We often hear that the body cannot survive longer than ten days without food. This has led to the nonsense of courses on "edible plants", trapping small animals, eating bugs, etc. No one seems to realize that the energy expended by such efforts likely exceeds the minimal caloric content of the "food". Actually, the body's tolerance of extended fasting is well documented--time in excess of 40 days has been shown for centuries. Indeed, mammalian physiology is well adapted for extended periods without eating. (This is the reason that calorie restriction alone is rarely sufficient for extended weight loss.) The woman in question wasted no time or energy in pursuit of food.
She also stayed put. Although conventional teaching might have called for her to follow the nearby creek downstream, she chose not to do so. (Apparently, the unfortunate woman had some emotional disorder which contributed to her predicament, so this may not have been an informed "choice".) Rather than wasting energy and risking injury by walking distances, she simply stayed put, stayed warm, stayed dry, and waited. There are not too many areas in the US where a lost person cannot ultimately be found if she waits long enough--especially after abandoning a car.
Sure, she made some mistakes (albeit possibly intentional) which led to her near-miss. Nonetheless, we should remember the lesson of Margaret Page before pontificating on wilderness survival to our students.
Monday, February 20, 2012
Northeast Wilderness Medicine Conference
Upstate New York will be hosting a major national conference on wilderness medicine from May 31, 2012 through June 2, 2012. A number of WM experts will be on hand, and the broad program offers something for everyone. Additional information and online registration are available at: http://upstate.edu/emergency/outreach/conferences/newm/index.php
Hope to see you there!
Hope to see you there!
Thursday, December 1, 2011
Wheezing in the Wilderness
Asthma is a big problem in the United States, and one which is growing annually. Somewhere between 3000 and 4000 people die from the disease in this country annually; this figure includes about 200 to 300 children. While I am unaware of confirmed asthma deaths in the setting of backcountry treks, the disease is so common it is inevitable that some folks with asthma will have difficulty in the wilderness.
Most specialists in asthma believe that the bulk of these deaths are unnecessary. Many of them result not from the lack of appropriate therapy but from failure to use well-established therapies in the appropriate fashion and time.
There is a major national initiative ongoing to improve all of this. One big component of it is the development of personal "asthma action plans" (AAPs). These are documents which are developed for individual patients with their physicians, which provide specific directions for treatment depending upon actual symptoms. There are several versions of AAPs, but all are predicated on the individual's assessment of his or her condition as "green" (good), "yellow" (not good), or "red" (awful). The plan provides specific medication suggestions for each zone. Here's a link to a nice example of an AAP:
http://cpnonline.org/CRS/CRS/pa_actionpl_art.htm
How does this relate to the wilderness? Although this system has become state-of-the-art for asthma care in the US, it has largely not penetrated first aid courses--any courses, not just wilderness ones. I recently reviewed over a dozen wilderness first aid textbooks and none even mentioned the AAP. Instead, they had a variety of generic recommendations regarding inhalers, perhaps enhanced by some attempt at explaining esoteric lung physiology, none of which were particularly useful. I guess that I shouldn't find this too surprising, since at a panel discussion in which I took part a while ago the representative of a major provider of wilderness first aid training commented that he had asthma himself and never heard of an asthma action plan!
Is there an "action item" for the wilderness educator here? You bet there is. Part of the pre-trek process in most programs is some sort of medical history/screening/release. I firmly believe that if any prospective participants provide a history of asthma, they must have an up to date personal AAP, a copy of which accompanies them on the expedition. Of course, there is also a need to be sure that the individual has an adequate supply of any or all drugs called for in the AAP.
What if someone does not have this? Although I hardly ever criticize fellow physicians (I know you'll find that hard to believe!), this is a time when it is appropriate to do so. Simply put, a physician caring for a patient with asthma in the 21st century who does not provide an asthma action plan is providing substandard care. This isn't just me--the Center for Medicare and Medicaid Services (CMS) has a standard for hospitals that patients with asthma must be provided with AAPs upon discharge. Failure to do so can actually result in hospital sanctions.
Therefore, I believe that programs have an obligation to their participants to notify them that they must discuss with their physician the development of an AAP and must bring one along with them.
Most specialists in asthma believe that the bulk of these deaths are unnecessary. Many of them result not from the lack of appropriate therapy but from failure to use well-established therapies in the appropriate fashion and time.
There is a major national initiative ongoing to improve all of this. One big component of it is the development of personal "asthma action plans" (AAPs). These are documents which are developed for individual patients with their physicians, which provide specific directions for treatment depending upon actual symptoms. There are several versions of AAPs, but all are predicated on the individual's assessment of his or her condition as "green" (good), "yellow" (not good), or "red" (awful). The plan provides specific medication suggestions for each zone. Here's a link to a nice example of an AAP:
http://cpnonline.org/CRS/CRS/pa_actionpl_art.htm
How does this relate to the wilderness? Although this system has become state-of-the-art for asthma care in the US, it has largely not penetrated first aid courses--any courses, not just wilderness ones. I recently reviewed over a dozen wilderness first aid textbooks and none even mentioned the AAP. Instead, they had a variety of generic recommendations regarding inhalers, perhaps enhanced by some attempt at explaining esoteric lung physiology, none of which were particularly useful. I guess that I shouldn't find this too surprising, since at a panel discussion in which I took part a while ago the representative of a major provider of wilderness first aid training commented that he had asthma himself and never heard of an asthma action plan!
Is there an "action item" for the wilderness educator here? You bet there is. Part of the pre-trek process in most programs is some sort of medical history/screening/release. I firmly believe that if any prospective participants provide a history of asthma, they must have an up to date personal AAP, a copy of which accompanies them on the expedition. Of course, there is also a need to be sure that the individual has an adequate supply of any or all drugs called for in the AAP.
What if someone does not have this? Although I hardly ever criticize fellow physicians (I know you'll find that hard to believe!), this is a time when it is appropriate to do so. Simply put, a physician caring for a patient with asthma in the 21st century who does not provide an asthma action plan is providing substandard care. This isn't just me--the Center for Medicare and Medicaid Services (CMS) has a standard for hospitals that patients with asthma must be provided with AAPs upon discharge. Failure to do so can actually result in hospital sanctions.
Therefore, I believe that programs have an obligation to their participants to notify them that they must discuss with their physician the development of an AAP and must bring one along with them.
Wednesday, October 5, 2011
What do ticks, heart attacks, and protozoa have in common?
I recently did a column in my wilderness health series in Adirondac magazine on the topic of ticks (http://adirondoc.com/publications/ticked_off_072011.pdf). I warned the editor that as soon as the column came out, he would be receiving irate letters. He didn't believe me.
The ink on the magazine was hardly dry when the first complaint came across his desk.
I was taken severely to task for minimizing the problem of Lyme disease among users of the outdoors.
Read the piece and judge for yourself. Lyme disease is a nasty affliction, but virtually always treatable with a short course of a common antibiotic; deaths from Lyme in the US are virtually unheard of. "Chronic" Lyme disease exists mainly in the minds of a group of unfortunate folks with some sort of chronic pain syndrome and a group of "specialists" who make a living from them. Hikers in tick-infested areas should take some simple precautions, but not consume much mental energy worrying about them.
The whole thing got me thinking about the irrational way in which those of us in the outdoor education industry decide what to worry about. It isn't just ticks.
I spend a lot of time working with challenge course programs, especially around issues of "medical screening". There have been a few (actually very few) cases of sudden cardiac death involving users of these courses, although on a per-participant-hour basis the actual risk is statistically at baseline (http://adirondoc.com/publications/sudden_death_2002.pdf). (Remember, over 300,000 people experience sudden cardiac death annually, and every one of them was doing something at the time!) This has not stopped some in the industry from arguing for exhaustive (and completely unvalidated) screening methods to select out those at risk. This has reached the ludicrous point of some arguing that failure to implement such screening is "unethical"! Of course, experienced cardiologists will tell you that they cannot predict the risk of sudden death in any specific individual, but this has not stopped facilitators from implementing simplistic checklists--preventing nothing but also potentially depriving folks who could benefit from such a program from participating.
I have commented previously on the silliness which has inflicted many outdoor instructors regarding the risk of water-borne giardiasis. Although the scientific data on this problem are abundantly clear, there continue to be programs which enforce water treatment strategies which are entirely unsupported by data. Some of these are so bizarre (keeping utensils which are "dipped" in suspect water separate from "clean" ones; flushing out the microliters of water caught in screw-top water bottle grooves) they seem more suited for the Book of Leviticus than outdoor education materials.
The problem with this sort of thing is that there actually are some very good data which should inform our decision making in these areas. Sadly, most outdoor education programs do not seem to integrate such epidemiologic data into their policy development.
We worry needlessly about water quality, while rarely enforcing hand sanitation--a far better way to address the spread of intestinal infection on the trail. We push for wide availability of "Epi Pens" without prescription to trek leaders, with virtually no data pointing to anaphylaxis as an actual problem in outdoor education courses. Of course, those who push for Epi Pens are not the ones advocating flu shots and immunization updates--a vastly more important intervention for a group about to set out on a lengthy expedition. Many programs insist on lengthy "woofer" courses and refreshers for their leaders, in the face of absolutely no evidence that such programs meaningfully impact safety, even if a fraction of their skills could be retained. Epidemiologic data clearly point to automobile accidents and drowning as the major causes of death on treks--have you ever heard of a program with a mandatory driver education or water safety recertification requirement?
In my "day job" as an academic physician, I am constantly surrounded by the drumbeats of those insisting that everything we do be firmly grounded in evidence. When I step into the outdoor education arena, however, it appears that unsubstantiated opinion, anecdote, and dogma regularly trump evidence.
We must do better.
The ink on the magazine was hardly dry when the first complaint came across his desk.
I was taken severely to task for minimizing the problem of Lyme disease among users of the outdoors.
Read the piece and judge for yourself. Lyme disease is a nasty affliction, but virtually always treatable with a short course of a common antibiotic; deaths from Lyme in the US are virtually unheard of. "Chronic" Lyme disease exists mainly in the minds of a group of unfortunate folks with some sort of chronic pain syndrome and a group of "specialists" who make a living from them. Hikers in tick-infested areas should take some simple precautions, but not consume much mental energy worrying about them.
The whole thing got me thinking about the irrational way in which those of us in the outdoor education industry decide what to worry about. It isn't just ticks.
I spend a lot of time working with challenge course programs, especially around issues of "medical screening". There have been a few (actually very few) cases of sudden cardiac death involving users of these courses, although on a per-participant-hour basis the actual risk is statistically at baseline (http://adirondoc.com/publications/sudden_death_2002.pdf). (Remember, over 300,000 people experience sudden cardiac death annually, and every one of them was doing something at the time!) This has not stopped some in the industry from arguing for exhaustive (and completely unvalidated) screening methods to select out those at risk. This has reached the ludicrous point of some arguing that failure to implement such screening is "unethical"! Of course, experienced cardiologists will tell you that they cannot predict the risk of sudden death in any specific individual, but this has not stopped facilitators from implementing simplistic checklists--preventing nothing but also potentially depriving folks who could benefit from such a program from participating.
I have commented previously on the silliness which has inflicted many outdoor instructors regarding the risk of water-borne giardiasis. Although the scientific data on this problem are abundantly clear, there continue to be programs which enforce water treatment strategies which are entirely unsupported by data. Some of these are so bizarre (keeping utensils which are "dipped" in suspect water separate from "clean" ones; flushing out the microliters of water caught in screw-top water bottle grooves) they seem more suited for the Book of Leviticus than outdoor education materials.
The problem with this sort of thing is that there actually are some very good data which should inform our decision making in these areas. Sadly, most outdoor education programs do not seem to integrate such epidemiologic data into their policy development.
We worry needlessly about water quality, while rarely enforcing hand sanitation--a far better way to address the spread of intestinal infection on the trail. We push for wide availability of "Epi Pens" without prescription to trek leaders, with virtually no data pointing to anaphylaxis as an actual problem in outdoor education courses. Of course, those who push for Epi Pens are not the ones advocating flu shots and immunization updates--a vastly more important intervention for a group about to set out on a lengthy expedition. Many programs insist on lengthy "woofer" courses and refreshers for their leaders, in the face of absolutely no evidence that such programs meaningfully impact safety, even if a fraction of their skills could be retained. Epidemiologic data clearly point to automobile accidents and drowning as the major causes of death on treks--have you ever heard of a program with a mandatory driver education or water safety recertification requirement?
In my "day job" as an academic physician, I am constantly surrounded by the drumbeats of those insisting that everything we do be firmly grounded in evidence. When I step into the outdoor education arena, however, it appears that unsubstantiated opinion, anecdote, and dogma regularly trump evidence.
We must do better.
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