NUTRITION

Too much of a good thing

Julie Flynn (Evan Barr’s mother)

This article has been written with Evan’s consent.

Orienteers rarely experience life-threatening conditions related to their sport. This is a story about such an event. As usual with these incidents, it followed a series of unfortunate circumstances, this time at the Christmas 5-Days. The condition is hyponatremia, and it happened because of heavy sweating and an attempt to recover from dehydration by drinking too much water.

Hyponatremia: deficiency of sodium in the blood. It can be fatal if the salt levels in the blood are too low. Sodium, potassium and chlorine are vital for every muscle cell contraction and every nerve cell transmission in our bodies. These salts are lost through our sweat and urine.

THE Christmas 5-Days promised to be an enjoyable opportunity for bush orienteering in some great terrain and time to relax with friends at Buckenderra. After having spent Christmas with relatives in Canberra, we drove (in two cars) to the first event site just south of Cooma. En route we bought our supplies, including sports drinks to help with hydration, knowing that we’d get pretty hot running on the first evening. The first unfortunate circumstance was that the shopping, including these drinks was in the parents’ car.

It was a hot day and, typically for the 5-Days, the first event was run in the late afternoon. Water on the courses ran out quickly, so that those of us who ran later and didn’t carry water, missed out. Thirsty runners had emptied the containers of water at the finish well before many of us arrived back. The second unfortunate circumstance was that Evan didn’t run with water, had none on his course and had none at the finish after his 7km run in the heat.

Soon after returning to the finish area following our run, Neil and I (his parents) headed off to Buckenderra, to set up our tent for the next four days in a good shady position (third unfortunate circumstance). We expected Evan and his sister Ilka to follow along soon afterwards. The kids didn’t get to Buckenderra until after dark; they’d got themselves lost relying on the ambiguous copied map from the program (fourth unfortunate circumstance). Some hours had passed since the orienteering event, and Evan was feeling very dehydrated, with headache and nausea. He tried to slowly re-hydrate but couldn’t eat dinner. Ilka offered to lend him her hydration pack for the event the next morning, and Evan agreed that he’d probably run with it. He wasn’t up to pitching his tent that night so, feeling sorry for him, a couple of us did it for him.

Next morning he wasn’t 100%, but decided to run anyway. Evan had been training consistently for 3 months, so he could run competitively, and dropping the second day would have been very disappointing. I had a late enough start to watch Evan finish, and noticed no hydration pack on his back. Speaking to him about it later he said he decided he didn’t need it due to the cooler weather in the morning. This was the next unfortunate circumstance. Later he reported that he hadn’t noticed water at any of the control sites, and there wasn’t any at the control indicated on the clue sheet. It was actually at a different control site to the one marked on the clue sheet, but he hadn’t noticed it. At the finish he headed straight for the water containers. He drank several cups of water after finishing.

Evan felt worse as the afternoon progressed, and recognising his headache as a sign of dehydration, drank as much as he could over a few hours. He drank mostly water, but included one sports drink and a couple of sweet carbonated drinks. His body reacted by vomiting, and he did his best to replace the lost fluids, as he was feeling worse. He and Ilka have estimated that he probably drank about 5 or 6 litres over the day.

Just before 4pm, Evan had a seizure, while sitting in the park in Cooma. Ilka and his friends called an ambulance, and put Evan in the recovery position. Ilka accompanied him to the Cooma hospital. It was very fortunate that this fit happened in town rather than at the campsite, and that there were people around who cared for him. Thanks go to Jim Russell and Daniel the Swede.

Evan spent the next 12 hours very agitated, disoriented and not conscious of anything except that he was very sick. He doesn’t remember anything except feeling very sick and being unable to see. The medical staff at Cooma were alarmed when they discovered fluid in his lungs and rang for advice from a specialist in Canberra. At this stage, Evan was breathing pure oxygen from a mask, as his blood oxygen levels had dropped, and was hooked up to a saline intravenous drip. Blood tests were ordered, and an ECG and a chest X-ray carried out. A catheter was inserted so that his urine could be measured. He was still vomiting regularly. It was very scary to watch our son going through all this.

After a couple of hours, Evan was airlifted to the Canberra Hospital where medical staff with experience of this condition could take care of him. Neil, Ilka and I followed by car, arriving close to midnight. He was in the emergency department, hooked up to the sophisticated machines that measure blood oxygen, pulse, blood pressure, and respiration rate. The beeping of this machine became very familiar through the night. Every time it faltered, we woke up.

Evan regained full consciousness at nearly 4.30am and wanted to know what had happened and why he was in hospital. He was shocked to find himself connected to so many tubes (particularly the catheter). A blood test that morning revealed that his blood salts were back within the normal range, and he was allowed to leave.

On the following day, Evan was able to get an appointment with a sports physician in Canberra. His case was interesting enough for the doctor to fit him in before leaving town for the New Year long weekend. Evan expected a check-up and advice on appropriate hydration for orienteering. He didn’t get much advice, but had another blood test, expecting the results 5 days later. The pathologist who looked at Evan’s blood test was alarmed by the very high levels of Creatine Kinase, an enzyme that indicates muscle damage. He tried to contact the now absent referring doctor. When that failed, he made some further calls that eventually lead to the

He was in the emergency department hooked up to sophisticated machines. The beeping became very familiar through the night. Every time it faltered, we woke up.

emergency department at Canberra Hospital. That evening, the doctor from Canberra Hospital rang us (we’d abandoned the 5Days, leaving our lonely tents where they’d been pitched on the first day), and asked that Evan return to hospital immediately. They wanted to flush out his system to make sure his kidneys were coping. There is a risk of renal failure with these high enzyme concentrations.

Evan had a second night in hospital, with an intravenous drip and providing regular urine samples. His blood Creatine Kinase level rose to over 21,000 during the night. The normal range for this enzyme is less than 200. He left the hospital the next morning when these levels had started to fall, but they were still around 19,000. Evan recovered from the hyponatremia, but it’s taking a while longer for his muscles to recover. They are still very sore some three weeks later. He won’t be running for some weeks yet.

I’m left wondering what we can learn from this story, so that it doesn’t happen again during orienteering events. Evan has learned a very important lesson or two. It’s important to replace not only water, but also salts soon after a sweaty run. Sports drinks are the easiest way to help replace both. It’s also very useful to have ambulance cover.

There is evidence that some individuals may be predisposed to hyponatremia. The trick is it’s hard to discover if you are one of them. So until there is evidence to the contrary, assume that you are susceptible. • Carry your own water when running a race. Do not assume the organisers will have water on the course. It may be short in volume, it may have spilt, or it could be in the wrong place. Hydration packs and belts (with small bottles) can be quite comfortable. It is good to be able to swig when thirsty, rather than waiting to get to a water control. A general rule of thumb is to drink 500ml per hour of race. For longer races or races in hot weather, you can fill the hydration pack with an isotonic drink rather than just water. • Learn to gauge how much fluid you tend to lose when exercising by weighing yourself before and after training runs of different lengths and in different temperature and humidity conditions. Get used to rehydrating with about the right amount for your body after each run. Digital scales are reasonably accurate and cheap to buy these days. Using them will help you know how much water is too much. Losing a kilo of weight does not mean you have dehydrated by one litre. The water lost during running is partly from sweat and partly from the metabolising of glycogen. You only need to replace the sweat component after the race. Certainly drinking beyond your body weight loss is over-hydrating. The Lore of Running has detailed information on the subject. • Always have spare water and sports drinks when attending orienteering events. The powder is cheaper ($10 worth of powder can make up 8 litres) than bottled sports drinks ($3.50 for 600ml).

Evan’s problems were the end of a sequence of events that led from dehydration to hyponatremia. There is not much that organisers can do to minimise the risk of hyponatremia. It is an individual runner’s responsibility to manage his or her fluid intake. But organisers can help minimise the risk of dehydration. 1. There is a culture in our sport of relying on the organisers for water. This can lead to problems if organisation slips up. If you are promising to provide water on the course, then you need to provide enough. The quantity provided must be sufficient for all competitors to be able to drink some, and its location must be accurately marked on clue sheets, so runners know exactly where to find it. If the terrain doesn’t make water drops easy to organise, plan the course around practical water placements. This is more important than the navigation challenge of the course. 2. Sufficient water should be available for all participants at the finish. In hot weather or at longer events consider providing water, with electrolyte powder added, at the finish to help people fully recover from their fluid and salt loss. It costs more than water, but could be a good investment in preventing further cases of hyponatremia. 3. If, because of workload and logistical problems, you are assuming orienteers will have their own water while running or after the event, make sure they know this well before the event.

Hydration – There’s more to it than fluids alone! Gillian Woodward

In the December’05 edition I wrote about hydration, briefly touching on electrolyte balance. Now let’s look more closely at the importance of getting our sodium and potassium levels right. These two electrolytes need to be kept in perfect balance for the body to function well.

NORMALLY blood sodium level is very tightly controlled, remaining within 136 – 142 mmol per litre. The main way sodium is lost from the body is through sweating. However, the blood level of sodium can also be reduced when large quantities of low sodium drinks such as juice, cordial, soft drinks or water are consumed. Overzealous drinking of such beverages prior to prolonged exercise performed in mild to warm conditions (when sweating is profuse), sets the scene for hyponatremia (low blood sodium levels of less than 125 mmol per litre) to occur.

A continued fall of sodium in the blood causes water to move rapidly into the brain, resulting in swelling. The faster and lower the fall in blood sodium concentration, the more serious the consequences. While very mild symptoms like nausea or stomach bloating may be experienced at a blood sodium level of 125 – 135 mmol per litre, a further drop to less than 125 mmol per litre produces vomiting, throbbing headache, swollen hands and feet, wheezy breathing, extreme fatigue, confusion and disorientation. Below a sodium level of 120 mmol per litre, respiratory arrest, seizure, coma, brain damage and death become more likely.

The athlete most at risk of hyponatremia is: 1) one who drinks too large a quantity of low sodium beverages before and during prolonged exercise; 2) the smaller, slower person who sweats prolifically or who has a very salty sweat; 3) those who rely too heavily on water as their main fluid; 4) a person with abnormal water retention (diluting blood sodium levels).

Drinking too much fluid, especially water, during exercise can cause problems too. Usually the kidneys are able to deal with such excesses, by excreting the fluid as urine. However, during exercise, the flow of blood to the kidneys is reduced (because blood flow to the exercising muscle is the body’s priority), and hence urine production is decreased by 20 – 60%. Consequently the retained body fluid further dilutes blood-sodium levels.

Prevention – Far better than cure

Many sporting organisations have compiled general recommendations/guidelines on hydration for athletes involved in competitive exercise. The wide range in quantity of fluid suggested allows for individual variations in body size, level of fitness, exercise intensity, temperature and humidity of the day, etc.

It is strongly recommended that athletes practise their drinking skills during training sessions, so they can work out an individual plan best suited to their particular needs. This hydration plan, of course, may still need extra modification according to different climatic conditions. The hotter or more humid the weather conditions, the greater the volume of sweat produced and therefore the larger the volume of fluid that will have to be drunk to maintain adequate hydration.

The general recommendations for fluid intake of physically active adults are as follows: • 2 hours prior to exercise, 400 – 600 ml of fluid should be consumed to allow time for excretion of excess water via urination. • 10 – 20 minutes before exercise, 200 – 300 ml consumed to top up fluid levels. • during exercise, 150 – 350 ml fluid consumed every 10-15 minutes, depending on individual toleration.

As I indicated in the December’05 edition of AO, sports drinks are the most appropriate choice of drink. They are scientifically formulated to replace not only fluid, but sodium as well and they have the added benefit of supplying extra carbohydrate for a continued energy boost. They can be used before, during and after the event.

For orienteers, this means that it is up to the individual to prepare with adequate hydration, carry their own supply of sports drink on the run (in a belt-pouch or backpack bladder) and have readily available recovery drinks available immediately after the event. Drinking a little extra water which has been placed out on the course can be helpful, but orienteers should learn not to rely on this as their major source of hydration. It makes much more sense to be independent where fluid is concerned.

Gillian Woodward is a Practising Dietician and has been providing advice in the field for over 25 years. She has been an orienteer since 1984.

Electrolytes & Hydration

Bill Gookin (San Diego Orienteering, USA)

How dehydration can affect your Orienteering performance.

The first symptom of dehydration is mental. Long before you begin to feel thirsty, when you are down less than 1% of your body weight (1 litre in a 70kg person) because of fluid loss, mental sharpness is affected. You don’t even start to feel thirsty until you’re down 3% of your body weight and, because you’re not thinking as clearly as you should, you may not even notice that you are thirsty, especially if you are trying to concentrate on a task ... like Orienteering.

This level of dehydration affects judgment, memory, reactions and the ability to make quick decisions. For me, my first sign of dehydration is when I can’t remember a word or name that I know ... you’ve been there ... the “It’s on the tip of my tongue” syndrome. Or I’ll stumble over a word, starting to say another word instead but not the one I wanted. One Search & Rescue instructor describes the sequence of dehydration symptoms as “mumbles, grumbles, fumbles and stumbles”. This amount of dehydration can affect everyone in their daily activities and you can imagine the effect on your Orienteering, “the thinking sport”.

Water, water everywhere

3-5% for every percent of fluid loss. Couple this physical decrease in performance with the even more significant decrease in mental acuity and you are really compromising your Orienteering results. And, as you get even more dehydrated, the effects begin to become more serious: you may lose track of the collecting features you were going to look for, miss that attack point and find yourself wandering around, not sure where you are nor how you got there. You know that you should relocate but aren’t thinking clearly and don’t do it because “you’ll figure out where you are any minute now.” You may even realize that you are dehydrated but, because of this “fuzzy thinking”, probably won’t even drink at the next water stop. There’s one advantage to using a “Camelback” or similar hydration system: you can drink without thinking.

So far your dehydration is having a negative effect on your Orienteering, both the mental and physical aspects: you’re making mistakes and aren’t moving as fast as you should. If it’s a nice day for Orienteering, partly cloudy and not too hot, you’ll finish, or even DNF, maybe not feeling too well and unhappy over a poor performance. It won’t help that the next symptoms of dehydration, along with the increasingly impaired mental functions, include a headache, irritability and loss of appetite.

If it’s hot and dry or hot and humid, these symptoms can progress rapidly from just having a poor day of Orienteering to becoming a casualty from heat exhaustion. In addition to providing the medium for all cell functions, water is the body’s coolant. With increased activity and high ambient temperatures, blood flow to the skin increases and evaporation of sweat helps keep the body’s temperature normal. As you become more dehydrated, less water is available to cool you by evaporation and, in addition to becoming more confused and irrational, your muscles are cramping, you have a splitting headache and you’re staggering ... you’re in big trouble from heat exhaustion and will be very lucky to find and make your way to the finish.

Electrolytes are the minerals that, like water, are necessary for cellular functions.

Precautions

Because the early effects of dehydration involve muddled thinking and that probably will mean that you may not drink even if you realize that you are dehydrated, it is important to make drinking before and during competition an automatic routine so you don’t have to think about drinking ... like using a “Camelback” or taking a drink at every water control whether you think that you need it or not. It doesn’t even really work as well to carry a water bottle in a pack unless you have a routine that requires no thinking.

For example, in the last day of this summer’s Colorado 5-Days (August 2005), I was doing pretty well in the first third of my course, visualizing well and “spiking” the controls, but then I must have gone right past a control, didn’t recognize a catching feature and spent much longer than I want to admit wandering around, searching for a feature I could recognize while telling myself that I needed to relocate and that I needed to drink ... and doing neither. Sound familiar? Finally, I hit a road, sat down on a rock to rest my leg, pulled my water bottle out of its pocket and drank more than half the contents ... and relocated myself. I kept the bottle out the rest of the course, drank from it frequently and at water stops ... and spiked the rest of my controls. A little hydration makes a big difference!

What about electrolytes?

Electrolytes are the minerals that, like water, are necessary for cellular functions. Sodium, potassium, calcium and magnesium are needed in the largest quantities and have to be replaced daily.

Sports drinks contain the electrolytes that are supposed to replace what you are losing and many of them can be of some help. All but one of these drinks contain more sodium than potassium because sodium helps to retain fluids. Unfortunately, this retention is in the tissues and not so much in circulation where water is needed to maintain blood volume for sweating and muscular and cerebral activity. Now this may be O.K. the day or evening before you compete but during the event and immediately after, you need to have the fluids in circulation and for this you need to have slightly more potassium than sodium in your replacement drink.

Unfortunately, almost all of these sports drinks and all energy drinks contain too much sugar and complex carbohydrates that have to be diluted and digested before they can be absorbed. This pulls water from the muscles, dehydrating you even further and can cause muscle and gastric cramps and intestinal problems ... remember that the function of most laxatives is to pull fluids into the intestines. However, all of this sugar makes the drinks sweet and makes you more thirsty so you’ll reach for another bottle. I think they call this “marketing.”

For most people, plain water sits in your stomach and sloshes around when you run. If you drink enough, hydrostatic pressure forces the water through the stomach wall and into circulation. This dilutes the blood and, as it passes through the kidneys, they get rid of the excess water ... and you’re still thirsty! Others can get by on plain water during competition but they need to be sure to replace the electrolytes they are losing, especially since the water is flushing out their electrolytes.

This can be very serious during extended efforts like marathons, multiday events and hiking in dehydrating conditions and there have been many cases where people have collapsed with symptoms of heat exhaustion but their fluid volume and blood pressure were up and their urine was clear. They had flushed out so much of their electrolytes by drinking plain water that many have died from what is known as “hyponatremia” which means “low systemic sodium” but it is almost impossible to be that low in sodium without being seriously low in all of your electrolytes.

Gookinaid HYDRALYTE

What about Gookinaid HYDRALYTE? I guess I’m going to have to mention this drink because we get so many wonderful reports from people who are using it. I formulated this drink after getting sick on Gatorade during the 1968 Olympic Marathon Trials. It worked so incredibly well that other runners wanted to know what I was drinking and one said that it helped me so it should be called “Gookinaid.” We added the “HYDRALYTE” after the staff at Johns Hopkins University Medical Center told us “You’ve got a great product, but you need a more clinical name.”

I’d made it to have the balance of electrolytes I needed to replace and to be innocuous in my stomach. This turned out to be just exactly the ratios and concentrations of the right ingredients for the most rapid possible absorption from the stomach into circulation, so fast and effective that emergency response teams call it “the oral IV.” Users have found it to be extremely effective in precise tasks to maintain mental alertness, judgment, coordination and quick decisions. Last Spring, while visiting the Grand Canyon, I was introduced to the Incident Coordinator for the National Park and the first thing he said to me was “Your stuff has saved a lot of lives here.”

And it can help you to be more successful in your Orienteering! ...also, if you drink it after your event, you’ll recover faster and feel better the next day.

Visit us at www.Gookinaid.com for more information about Gookinaid HYDRALYTE and how it can help you in all you do.

Reprinted from Orienteering North America, Oct/Nov 2005.