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Posts tagged ‘Water’

Why do we get muscle cramps while training part 2

As I mentioned in my last post, scientist still don’t know why we get muscle cramps while exercising. The old theory was the electrolyte depletion and the new one is the muscle fatigue. I gave some flaws of the electrolyte theory, but this does not mean that I totally disregard that theory. As there are some people who actually lose salt at a rate five times faster than normal. Salts are essential to hydration despite of that mineral’s reputation for drying you out.  A body short of salts won’t deliver the water efficiently to the muscles. So even if you are drinking bottles and bottles of water, nothing will happen. The thing is that most people don’t lose salt so fast so, in my opinion, most of the exercise muscle cramps come from fatigue. There is also a difference between electrolyte depletion cramps and fatigue cramps. Electrolyte depletion cramps are much more serious, they affect more than one muscle and stretching won’t alleviate the cramp. Fatigue related cramps aren’t that serious, and usually by stopping the activity and stretching the cramp will go away.

So what can we do to try to avoid the muscle fatigue cramps? Go slower, decrease the intensity or train better, let me explain. We often get these cramps in competition and not while training. This is usually because, when we are competing, we are going faster or more intense than during practice due to the adrenaline or to due the mere fact that we are competing to get the best results. If the body is not trained to go at that intensity it will get tired faster, meaning a higher chance of getting a cramp.  And that is what the studies have shown, namely that the increased running speed is what predicts who will get the exercise associated muscle cramps. (1-5)

Hope you liked it.

  1. Schwellnus MP, Drew N, Collins M: Increased running speed and previous cramps rather than dehydration or serum sodium changes predict exercise-associated muscle cramping: a prospective cohort study in 210 Ironman triathletes. Br J Sports Med, 1-7, Dec. 9, 2010
  2. Schwellnus MP, Derman EW, Noakes TD. Aetiology of skeletal muscle cramps during exercise: A novel hypothesis. Journal of Sports Sciences, vol.15, pp 277-85. 1997
  3. Schwellnus MP. Muscle cramping in the marathon:aetiology and risk factors. Sports medicine. Auckland, NZ 2007.
  4. Schwellnus MP. Cause of exercise associated muscle cramps ( EAMC)–altered neuromuscular control, dehydration or electrolte depletion?
  5. Braulick KW, Miller KC, Albrecht JM, Tucker JM, Deal JE. Significan and serious dehydration does not affect skeletal muscle cramp threshold frequency. Br J Sports Med, 1009 Jun:43(6):401-8
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How much water do we really need to drink?

I think we have all heard at one point or another in our life that drinking 2 liters of water per day does wonders to your mind and body. But is this really true? Let´s find out.

2 Liters per day is about drinking 8 glasses of water per day, and if you have ever tried doing that, you have realized that you spent a lot of time in the toilet. So, where did this mythical number come from? Why 2 liters and not for example 1.5 or 3 liters?  Well, it probably started from a study done in the 1940s, where researches calculated that 2 liters is how much water a person’s body consumes in 24 hours, so WALLAH, there you have it, that´s where the magical number comes from. But what also came out of that study, and what a lot of people don´t know, is that we get much of the water we need each day from our food, and this does not include the number of drinks like coffee and tea most of us consume every day. And NO, coffee and tea DON´T DEHYDRATE YOU. Although coffee and tea may act as diuretics, the amount of dehydration caused by these beverages is not equivocal to the volume of the fluid. Caffeine has been shown to cause one milliliter of fluid loss per milligram of caffeine. So let´s give an example to explain.

  • A normal cup of 260 milliliter of coffee has around 90 milligrams of caffeine, so if the caffeine causes one milliter of fluid loss per milligram you would still have 170 milliliter of liquid, So, in other words you gained 170 milliliter of liquid, that´s called hydration.

So we know half of our body is made up of water, we know water is vital to keep the important chemical reactions in our body functioning. But the idea that you should drink 2 liters of water per day has absolutely no evidence to back it up. So what should you ? Drink when you are thirsty, if you have to drink more than 8 glasses per day do it, if you have to drink less than that also do it. In other words, listen to your body and you will be perfectly fine.

References

Fink H, Burgoon L, Mikesky A. Practical Application in Sports Nutrition. Jones and Bartlett Publishers, Inc 2006.

Grandjean AC, Reimers KJ, Bannick KE, Haven MC. The effect of caffeinated, non-caffeinated, caloric and non-caloric beverages on hydration. J Am Coll Nutr. 2000;19:591–600.

Food and Nutrition Board of the Institute of Medicine. Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate (2004). Accessed October 11, 2006.

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