The Issue of Cramp

Just a few words before I begin

I have decided to start a writing a series of blogs on the issues that exist around endurance sport. Most likely about sport science but not necessarily so. These blogs will be different from my normal unintelligible ramblings that I normally put up. I will try and include thought out arguments or facts from as many sources as I can find. I am thinking of doing about 1 a week and basing them around some issue or event that has occurred during the my training or planning of the my training program. Though, as I don’t necessarily have a issue every week, it might be based on something that I have read. I want to be able to create discussion through these blogs, for I am sure that there could be many opposing views to what I write.

I want to do this for two reason:

1. I have a tendency to read a lot of stuff in books and the internet. But I sometimes forget about what I have read. By writing about it and clarifying my point of view on what I have read, I will be able to remember and understand my point of view better.
2. I thought when I first started this blog, “I don’t care how many people read my blog”. But as it turns out I do. Should I be ashamed to admit that I am looking at my blog stats, and feel disappointed when I only get 20 views in a day. But then considering the general every day stuff I write about I don’t blame people for not wanting to read. So with this series of blogs I want to encourage more people to view, and hope that more people will add there comments and views on what I have written.

Please note: I am going to reference all my sources at the bottom of the page, but I ain’t at university any more so I am not going to qualify every statement I make with a reference. I am sorry to the authors and the purists out there, but that’s my worse memory from University (adding a reference to each statement) so I am not going to make myself suffer through that again.

The issue of cramp

So this week I am going to start with the issue of cramp. Cramp is not something I suffer from to any great degree. I hardly never suffer from cramp when training, and is only in races that it has truly troubled me to any great degree. In fact on the coast to coast run, when I got cramp, I truly didn’t know what to do about it, as I never really suffered before to any great degree. Though this week when I was on my run at lunch time for 90min my legs started cramping, but I think that was because they were so cold.

There are 2 theories around what causes cramp in endurance athletes:

1. Electrolyte depletion theory: This is the most common theory out there, this is one of the reasons that us athletes drink and spend all that money on those (not so pleasant) electrolyte drinks (raro would be cheaper). Basically, for those of you out there that don’t know, the principle is that we sweat out so much electrolyte that the if it is not replaced, this causes the muscles to cramp.
2. Muscle Fatigue and Spinal Reflex theory: This is a more recent theory and was develop because there was serious flaws in the first theory.Now its harder to explain because it is all to do with the physiology of how the muscles work. But in very lamens terms, the muscle firing system gets fatigued during exercise and this causes the muscle to contract involuntary.

A person who is medically dehydrated and has low electrolytes will cramp, but all their muscles will cramps, not just 1 or 2, which is the case with exercise induced cramp. The problem with this first theory is that the during exercise when a person sweets they lose more water than they do the same percentage of sodium, so actually the sodium concentration has actually increased. Oh this too time consuming to explain, and I can’t do it as well as these guys so go here to get all the facts. Basically when we sweat the sodium concentration increases, then stimulates the thirst response, and you drink water which will bring the sodium level back to normal. It would be my possible conclusion that we have been tricked into drinking electrolytes because we have been told to over drink, making us more likely to be over -hydrated. So if we follow the drink when thirsty principal, we wouldn’t be replacing all our water loss, only about 50 -60% , this is completely against all hydration information I have been told. I am unsure what will this mean a person is going for a extremely long period of time (by long I am thinking 24hrs, as 10hrs proves to work OK in this theory)

Also the body is quite good at regulating its sodium levels, without any external source, sodium isn’t just available to it in the cells, there are other places it can draw it from, including the bone. Sorry I am getting away from cramp. I think hydration and fluids will be a lead on topic from this one.

The electrolyte depletion theory has been around for over 100 years (workers of the Hoover Dam were given salty milk to prevent cramp), and has been popping up every decade or so. And people have been using circumspectial evidence to prove that this theory is correct. The theory has also been supported by the Gatorade Sports Science Institute… now if you can’t see the problem about research that has been done to support the profits of its owner, than go away and think about it.

The Muscle fatigue theory, says that the muscles that are more likely to cramp are those that cross 2 joints. For example when swimming, the toes are pointed, and the knee is also bending. This means that there is a higher chance of getting cramp, the same can be said about the cramp you get when sleeping.

From my experience the muscle fatigue theory seems to fit my experience a lot better. The only time I have got cramp is in places where I have pushed my muscles beyond what they had before had to achieve. Made them work so much harder.

The trouble with researching cramp, is that it is difficult test in a lab, so they (the scientists) have trouble truly understanding it. But the research they have done in the field seems to indicate that cramping athletes have the same sodium levels as there fellow non-cramping athletes.

So conclusion, I think that electrolyte drinks have been over marketed, and I think I need to seriously consider removing them from my training nutrition. But even though I have read the supporting evidence to show that this has merit, I am a little scared to remove them. The muscle fatigue theory is in its infancy and a lot more research needs to be done to understand it further. I have a few questions in regards to this topic, is there ways of helping the muscles overcome this, will compression tights help? I will also like to know how does cramp stop works?

References

The science of Sport Blog – To get the actual un-paraphrased truth, visit these guys blog.

Speed, Agility & Power: Gatorade Sports Science Institute