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Sunday, February 01, 2009

Did I suffer Heat Stroke or was it Hyponatraemia?

"I went for a 25km walk at the weekend and was badly affected by the heat, after about 15-20km. We were walking across hilltops, in the wind, with little shade. I came down the hill, through the bush, at an early spot and managed to get a bus home.

The symptoms were mental tiredness (I just wanted to sit down, then sleep), a headache, dizzy spells, feeling a bit 'spaced out'. I had drunk most of a Mizone and had drunk plenty of water. In fact, I probably drank too much and had a full feeling in my stomach. I had eaten meusli for breakfast, mueli bar, stuffed potato, a sausage rolls (later two as they had salt).

I felt much like I had when tramping in hot weather overseas a few years back. At the time I had some 'enerlite' re-hydrations salts, but a local prescribed me a salty tomato soup with plenty of garlic with dinner, and that sorted me out.

The previous weekend we had walked further distance, but it was not so hot and I did not feel the same way. Also, the terrain was probably flatter.

I think the problem is lack of salts - I may have sweated a lot out in the hot, windy conditions, and tried to fix it with too much water.

I am concerned this might happen again. Is there a nutritional hint about food I can eat before going out in heat? Is it a matter of drinking more Mizone/Powerade? Do you know if the powdered Powerade as good as the stuff you buy in the shops?"

Tobin, we will never know for sure whether it was overheating and dehydration (Heat stroke or heat exhaustion) or a case of too much water (Hyponatraemia). The symptoms can be nearly indistinguishable. I am guessing that you suffered the former. It is quite easy to overheat when lugging a back pack up and down hills. The high effort and slow pace do not give much benefit of a self generated breeze and the back pack does not allow the escape of excess heat via the back. Please read these articles about hyponatraemia.

The sure way to find out what is happening during these hikes is to get into the habit of weighing yourself before and after. Record everything you drink. If you suffer these symptoms again and you have gained weight during the hike, then you can assume that your body is excessively hydrated. If you have lost weight then you can work out how much you should be consuming from now on in similar conditions. The best way to do this is to use a set of scales that give you a break down of body composition. Please read this article here about body composition and hydration.

For example, my daughter and I went for a 1hr 40 min run yesterday. She lost 1.2kg (1.2 liters) and I lost 1.8kg (1.8 liters). We drank nothing during the run, so I now know that I need to drink about 1 liter per hour of running in similar circumstances; whereas my daughter can get away with a little less. When we get home, we can weigh ourselves and drink the equivalent to the difference in weight over the next hour or so.

I like to use Schuessler Tissue Salts to replenish the salts lost during intense or prolonged exercise. The brand I stock are the Active Elements brand. Please read these articles here about tissue salt replacement for athletes.

I do not like the pre-made sports drinks. There is nothing healthy about them with their synthetic colourings and flavourings and they tend to be among the most acidic of drinks. For waht they are they are expensive. It makes no sense at all to add more acid to a body that is already struggling to offset acids like lactate. Please read these articles here about acidity and take note of the "Acidity Chart" here.

The ones you make up yourself are better.

But here is an even better option for activities like day long hiking - Balance Ultimate Recovery. It works perfectly as a sports drink and has no artificial colourings or flavourings.

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1 comment:

Anonymous said...

I recently came across your blog and have been reading along. I thought I would leave my first comment. I don't know what to say except that in our country we just only walk on exercise by the time of 5-10 in the morning because when the time reaches 11 and above, the sun may affects our skin and health.

alexis scotts