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The sight of runners walking up from Esk Hause to Scafell in the Wasdale is traditional, but not always necessary. The reason for walking, apart from injury, is that they have either run short of energy, (muscle glycogen), or they have de-hydrated.
The body is a marvellous machine; the analogy I like to use is the car. As long as you keep topping it up with fuel and ensure it’s not short of water, and don’t exceed its speed limit, it will serve you well.
One of the most misunderstood aspects of energy expenditure is the volume of fluid that the body uses when working at a high capacity. The second is the percentage volume of the body that’s occupied by fluid. In young adults the percentage of body weight represented by water will average about 57% for males, and 47% for females. So if we have an athlete weighing 10st (63.5kg) and rung him out, he would weigh in, (shorts and all) at approximately 4 stone (25kg)!
A simple known fact, is that to lose 2% of body mass, in this case approximately 3lbs (1.36kg) will reduce performance by up to 20%. When it falls to 4% loss, 6lbs, you will probably be walking and not feeling too well. Once it falls to 6% (9lbs) you could be in real trouble.
When your body is short of water it correspondingly depletes its electrolyte level. Homeostasis is affected and all sorts of imbalances go on inside the body. The cardiovascular system has to work harder to pump blood around the body, which affects your performance.
To understand the principle of drinking what is possibly considered ridiculously large amounts of water, we need to look at what the body can do when the right amount of water, and fuel, are topped up at regular intervals.
A young 0/60 vet from Horwich set off in April 96 to run the Joss Naylor Lakeland Challenge from Pooley Bridge near Ullswater, to Greendale Bridge at Wasdale. His time limit was 18 hours in which time he had to cover 48 miles and climb 16,500 feet. In fact he did it in 16 hours 56 mins. The reason this little story is told was that he, along with others, was initially rather sceptical of the excessive amount of water prescribed, along with the energy content of over 4000kcal.
The formula that was used was as follows: He weighed in at around 70kg and we knew the distance to be covered was 77km. Knowing the recognised formula of 1kcal per kg of weight, per km of distance (allowing for all the climbing with extra food and snacks) gives the calculation of 70 x 77 = 5390kcal. Not wanting him to have all his energy by fluid we settled on 4000kcal with a pure carbohydrate hypertonic drink.
At 80kcal a scoop, 50 scoops were put into 10 litres of water, which he consumed over the 17 hours, much to his surprise. He did get a little help from the support crew in encouraging this feat, especially as it was less for them to carry. He duly arrived at Greendale Bridge an hour inside the time, after successfully negotiating some arduous sections, some covered in snow. His condition at the end was to say the least amazing, he looked fine.
Most runners are unaware that their feeling of fatigue can sometimes be just a case of mild de-hydration. If you work on the simple rule of at least a pint an hour, with the necessary energy content you won’t go far wrong.
Drinking en-route is obviously only necessary if the duration of the race demands it, but hydration before any race, even short, should be a matter of course. Also be aware of the diuretic influence especially of alcohol taken the night prior to a long run.
The availability of water can be a tactical ploy in any medium or long race, good reconnoitring of the race route is essential, especially if the weather has been particularly dry.
The easiest and quickest way to take water from a stream is to have a plastic bag containing the necessary carbo powder. Remove it from the bum-bag before the stream is reached; dip it in with the top open. In this way you can scoop a good measure, which you can drink over the next 100m or so - on the run of course! The technique is to make a seal by folding back the top of the bag and squeezing it tight. You then push the forefinger in to the opening on the top of the bag creating a small hole which you seal against your mouth and squeeze the bag to force the water out.
If you find that no water is available over the course or part of it, then good preparation either from pre-reconnoitre planting, or friend’s en route is essential. A hot day on Ennerdale after Pillar can be a problem without water. Although most runners like to eat something substantial on long ‘A’ races, carbo powder is all that is required - trying to eat a chocolate bar climbing Gable can add minutes to your climb.
HEAT EXHAUSTION (38°C) This is caused by excessive sweating combined with an inadequate water intake.
Signs & Symptoms
Management of Heat Exhaustion:
HEAT STROKE (40°C) Developed from heat exhaustion.
Signs & Symptoms
Management of Heat Stroke: