It's Not a Banquet, It's a RaceFacts and Prejudices on Supplementation of Fluids and CaloriesI do hope I will be forgiven for not delivering sharply demarcated advice on this complex subject. The reason: we weren't all made on the same conveyor belt, nor were we made at the same time.Aging by itself makes it harder to retain fluids when we are short on them, and to excrete them, when overloaded. On top of that, a long list of medications can cause inappropriate retention of water.
It is a better-trained athlete who can sweat more, not the one, who barely sweats and provokes great admiration. (S)he is just not trying hard enough or is running out of fluids. A generation ago ladies with blue beehive hairdos thought showing disgust for sweat confirmed their ladylike upbringing. The level-headed Marge Simpson is more modern, of course.
It is still a puzzle to me how we have come to accept the term "fresh smell of ammonia." A matter of concentrations, I assume.
Some think that exercise induced increase in plasma volume is just acclimatization to heat produced by exercise. This increase dilutes the red blood cells (plus others) causing an apparent anemia. Of course, this may be real, since athletes are not immune against the ills of humanity, and also because of losses of iron in sweat and urine (pounding red cells in the soles of the feet may cause the red hemoglobin to be freed from them and excreted in the urine. Some people bleed from the bladder where it hits the pelvic rim. This should not be a self-diagnosis).
I have a theoretical prejudice against ice collars, since those will cool the blood going to the brain and thus must give it the message that the body is cooler than it really is, which might slow down body's cooling efforts. I also try to keep the racing effort under the level that requires stealing blood from abdominal organs (guesswork only), and to stay fully supplied with water, salt and sugar. Even 2-3% decrease in body weight due to dehydration can slow down performance. To get enough calories in sports drinks or my own replacement for those (see below), I am forced to drink large amounts, and in Hawaii that has worked well. I needed no solid food calories to ingest the maximum amount of the carbohydrates which the body could absorb, more than one gram per minute.
Since I was a study subject in a few Labman studies, performed by reputable researchers like Pam Douglas M.D., Mary O'Toole Ph.D., and associates, my electrolytes, creatinine and hematocrit were checked before and after races. I am happy to report that their levels showed no significant change. I drank only sports drinks and no water in addition. When one drinks too much water and takes in too little salt, water seeps into the cells (salt's sodium, which stays outside the cells, would normally keep water out, but not if the amount of sodium is decreased). Cells swell, and since the brain is enclosed in a rigid box called skull, confusion, lack of coordination etc. can develop, and worse.
These problems are preventable. According to some, by restriction of fluids. I doubt that is correct; I interpret that for my own use as no CLEAR water. Drinking clear water takes up space and time in which I could have resupplied myself with salt and sugar. I try to get enough salt, since I train and race and sweat hard. I have read the recommendation for 1 gram of salt per hour, but have tried to take about two. I assume that enough (but not too much!) salt will keep water outside of the cells and in the blood: enough blood volume means better circulation in the kidneys, so they get a chance to try to maintain normal salt and water level in the body, and to correct our errors. They can't accomplish that, if they get too little blood to filter.
Since in Hawaii the aid stations are five miles apart, this is just right if you ride close to 20 mph. (not into the wind, I bet). In that short time I never "bonked." To be sure that I don't reach the next station with bottle not yet empty, I flip up the top and drink it in one breath, coasting, and with this brief rest usually catch those who got away from me in the meantime. I no longer use the straw setup, so now I can again mount a helmet mirror on the stem. Now I can keep my head down longer in the headwinds (the tail of the helmet sticking up in such position has been shown to actually decrease drag in the wind tunnel, much to everybody's surprise).
Fructose has the theoretical advantage of raising blood sugar (glucose) with some delay, since it has to be changed into glucose in the liver first. It has a very practical disadvantage that it can upset your innards in large amounts. Some drinks have a little of it added, because it is very sweet. I buy regular table sugar in boxes of cubes, which weigh just under 4 grams each. Eight of those in a standard 16 oz. bottle gives 32 grams in half a liter, or 64 grams in one liter (=1000 grams of water), thus about 6.5% solution, close to 6-7% sports drinks. If I don't like the race drink, I provide three hours' supply of salt and sugar by putting 90 sugar cubes in a 32-oz. (1 liter) bottle. A #4 capsule (found in pharmacies) filled with fine salt contains 0.9 grams, which equals 15 mEq of sodium for those, who prefer to operate in those units. I owe thanks for this practical information to my old friend and avid cyclist Marjan Kordas, professor of pathophysiology in my country of origin, Slovenia). Therefore I shake six capsulefuls in the same bottle, fill it with water, and mount it behind the seat. Low on the aerobars, it is easy to suck from that level through a long tube (I use one with 3/16th inch or 4mm inner diameter) which is attached to a stiffer tube in the bottle, so it wouldn't curl up from the bottom. This year I may eliminate the bottle carrier by using a Camelback and refill it after 3 hours, so I will carry only a liter at a time.
I get about the same amount of salt and sugar as I would from an average sports drink. How does it taste? Very sweet and very salty. It tastes only somewhat better than your legs feel, but that taste still symbolizes strength and endurance to suggestible suckers like me.
A friend, subject to cramps, takes a Tum (400 mg of calcium) every few hours with improvement. This is not backed up by studies so far. In training I drink a cup of milk (300 mg of calcium) when I anticipate much sweating. It is a bit disturbing that in at least one study, triathletes had no more calcium in the bones than couch potatoes. Maybe the loss in sweat is the cause, and maybe inadequate dietary intake in some cases, or too high protein intake. Protein burns down to urea, which has to be flushed out through the kidneys, thus increasing calcium losses.
I was taught during my medical training that stomach could only pass 1.2 liters an hour. This datum (yes, "this data" is wrong) has cascaded from textbook to textbook and finally sunken out of sight with other prejudices, including the one that race like the Ironman would be dangerous to older folks, even though trained. There have been no deaths in the 20 years and among 20 000 competitors in Ironman Hawaii. We can only imagine the reaction of those olympic committee officials who thought women should not run marathons, when they saw them do it following 112 miles of cycling in headwinds. I would like to have seen their faces when they read how Paula Newby Fraser beat all the Ironman field except for the top ten men in 1988. Or how Julie Moss' came in third overall behind Dave Scott and Scott Molina in Ironman Japan in 1985. I can't help digressing, these are fabulous facts. I hope they help your adrenalin production as much as they help mine. This adrenalin is not manufactured commercially, like in stadiums.
This loss, however, could be partly accounted for by losing the weight gain from pre-race carbohydrate loading (that deposits in the muscles about one pound of glycogen which binds three pounds of water), by burning a pound of fat or more, and by getting dehydrated about 2% of body weight or 3 pounds. It is clear that losses are noticeable, especially in the lava fields, where I saw a spectator fry an egg on the asphalt for special effect. I hear someone measured the temperature one foot above the asphalt at 140 F. which doesn't matter much, especially if you avoided "hot foot" by picking shoes with light colored soles. It is remarkable that one feels very little heat, partly due to the wind, and partly due to efficient, voluminous sweating of a well acclimated body.
When you get no salt in the swim (except in inhaled sea water), and start sweating on the bike, aldosterone hurries to get back to work, but in the meantime you are one or two bottles behind, and it is try-to-catch-up from here on. It is hard enough just to keep up with the losses, since, during a hard effort, there is very little blood going to the gut to absorb food or drink. (I had a banana on the bike during a half Ironman in Texas, and after the ensuing half marathon, I threw up the banana which was still waiting around in the stomach for something). When we land after the swim, my salt conservation mechanism is at least not turned off and is already in a miser mode; thus it is easier for me to make do with the amount of salt I get in on the spot and later on the course.
I would say that by then it is very late, but it all depends on the capacity of your bladder. It is easier to judge, where you stand (so to speak) in producing urine if you have a smaller capacity. If you are making none, trouble may be coming. The kidneys likely aren't getting anything to work with, and cannot straighten out the consequences of your overambitious underthink.
Mincing in place helps very little.
On the run I had to stop a dozen times with fast osmotic diarrhea, while chasing a person in my age group reported by three different people to be ahead of me. I still hadn't caught the phantom man running between me and qualification for Hawaii, so I pushed through pain, and inadvertently took 45 minutes off age group record. This showed on my lack-luster race in Hawaii six weeks later. I was lucky that everybody else had a bad race, too. The moral: frequent sit-downs can wreck your rhythm and raise the dickens with your chemistry. As always, I was aware of the rule that you should never use anything for the first time in a race. I ignored it, satisfied that I had that knowledge. The other moral: knowing you are committing an error gives you only intellectual comfort.
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