We have all suffered from some form of cramps in our lives, and we all hate them, especially when exercising or competing. I in particular am a great sufferer of these horrible yet interesting phenomena. There are many theories that discuss the reasons behind cramping. I will discuss the most commonly thought perpetrator – the theory that uses low salt or electrolyte levels, and the newer theory, to do with muscular fatigue and certain receptors within the muscle.
The theory that uses the old thought that the loss of electrolytes (for example - sodium, magnesium, potassium, sometimes referred to as salts) through sweating and dehydration in hot weather to be the cause of cramping. However research has shown many times over that in people who cramp, electrolyte and dehydration levels remain relatively the same compared to those who did not cramp or are usual sufferers of cramping. Another problem I have in particular with this theory in relation to my experiences is that I often cramp up when swimming, even in coldish water, when I am not sweating and my body is immersed in cool water, however when I go for a long jog, I usually don’t cramp and while jogging it is hot and I am sweating profusely, so then what could be causing my cramping..?
The other theory I would like to discuss is a muscle fatigue theory. It is to do with increased alpha motor neuron activity. These neurons innervate muscles and are responsible for initiating muscle contraction. These alpha motor neurons increase in activity during exercise resulting in more muscle contraction. Now within muscles and their tendons are two mechanoreceptors (detect mechanical change), a Golgi Tendon Organ (GTO) which detects increased contraction and tension in muscles and relaxes them before they are damaged, and Muscle Spindles which detect over stretching of muscles and contract the muscles when they are over stretched before they get damaged. When these two are in balance everything is fine. During usually long bouts of increased activity, muscle spindle activity increases and GTO activity decreases (more contraction, less relaxation) which result in a muscle cramping.
Another side theory to this muscle fatigue theory is that muscles prone to cramping are often muscles that cross over two joints such as the gastrocnemius (muscle of the calf group) (ankle and knee joints) , yes you know what a calf cramp feels like, the hamstring group (hip and knee joints) and the rectus femoris (hip and knee joints) (part of the quadriceps). Now these are three of the most common cramps experienced in activity. This is thought to be because muscles most often cramp in shortened positions, and a muscle that crosses two joints can be shortened that little extra (if your toes are pointed down – plantar flexion, and your knee is flexed, your gastrocnemius is shortened further that just from pointing your toes down). In a shortened position your GTO has even further decreased ability to relax the muscle and increased contraction can result in a cramp.
The most simple way of relieving these cramps are to passively stretch the muscle out using your hands for example. This increases muscle tension and activates the GTO which then relaxes the muscle again and relieves the cramp.
The mechanisms behind cramping are not set in stone, but theories do exist, some with more merit than others. So next time you cramp up, don’t just jump for your electrolyte drink or your old faithful banana. Maybe think about a nice quiet stretch and some rest, maybe, just maybe it’ll work for you too…!
JJ
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Hi JJ,
ReplyDeletePlease give me your opinion on the use of the Inversion Bed (Hanging upside down by the feet)
I try to use my bed twice a week to exercise by touching my toes and using weights with my arms.
Many thanks Mary
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ReplyDeleteHi Mary
ReplyDeleteI have had a look into inversion therapy and inversion beds and there is limited research and information that I could find other than actual stockists and promoters of the beds themselves. Thus this information can always be viewed skeptically.
Many benefits are reported such as decreased spinal compression, increased flexibility, and blood flow improvements to the head which is said to aid in brain function and flow of blood to the hair (the head is above the heart and circulation to these areas is usually against the force of gravity).
My opinion as a sport scientist is one of skepticism. I always view things with limited research and hard data with skepticism. I do not disagree with the benefits mentioned above but I do not believe they are something we are missing in exercise or that the benefits of inversion are so amazing as much of the information (written by people who sell the equipment) says. So by all means carry on using your inversion bed, if it relieves pain in your back (the most common use) then by all means go ahead and you can perform many stretches of muscles in your body and it is in no way a bad way of exercising, but I just don't think it is a revolution that everyone is missing out on.
There are also certain health risks with inversion therapy that arise in a lot of write ups I have read including increased blood pressure, problems for pregnant women and problems in people with eye disease. But as I have said there is research but very little in these fields and more research needs to be done in order to come up with real ideas about inversion therapy.
Take a look at this link where I found a lot of useful information.
http://www.energycenter.com/grav_f/freq_ask_quest.html
Hey there guys. Interesting article.
ReplyDeleteI was however wondering if you could give me some advice. I really love playing squash, but worry about an old ankle injury (torn Deltoid ligaments involved) What can i do to strengthen my ankle and/or warm it up before i play squash? It hasn't given me any trouble recently, but it tends to feel a bit sensitive after a hectic game of squash.
Any advice or input would be greatly appreciated.
Sulubezi
ReplyDeleteFirst of all it must be noted that we are more in the field of exercise training and exercise science, the person you need to see is a biokineticist. I will get a number for you for the university biokinetic lab. I will try to help you though.
A deltoid ligament injury is not as common as lateral ligament sprains. It is a very large, strong ligament and the action of eversion (mechanism that would sprain the deltoid ligament) is less common than inversion when injuring the ankle.
If pain is still present after playing squash, you might need to look at your rehab process and how well you followed it and what was done. You might possibly have muscular imbalances and require some strength training and possible some proprioceptive work, which is like balance training and it incorporates awareness of limb position and strengthens all supporting structures of the ankle and knee with regard to proprioceptive training for that area.
I will forward a number as a comment on this post.
JJ
nice article guys.
ReplyDeleteprobably myth busted i say. usually i can induce a cramp simply by yawning and stretching if i put enough effort into it. i can achieve this any time of the day, even if no form of exercise has been done, and hence, this has alwasy made me skeptical of the electrolyte theory.
however, i have always been the first person to cramp on the sports field, usually calf cramp or ham string cramp. why do you think i am so susceptive to cramping, even when i take further precautions than most by stretching and warming up more than the average person. this even occurrs at periods when i am considerably fit.
what can i do to prevent it or am i doing something wrong completely?what piece of the puzzle am i missing?
poncho_les
ReplyDeleteI am exactly like you with cramping. I always get cramps so I have always wondered how and just like you I have also always been able to make myself cramp at the drop of a hat. Your point about putting enough effort in and making a cramp supports the muscle fatigue theory - shortened muscles pushed to the limit = cramp.
Now about your cramps you still get...
As you said even when you are fit and taking precautions. Warming up migh not do anything for the cramping process as the fatigue theory states that when the muscle is fatigued and the mechanoreceptors (the GTO) and muscle spindles are not properly balanced etc... Warming up is not really going to prevent you from getting muscular fatigue.
But low electrolyte levels can cause cramp, but the argument, which has been proven many times, is that electrolyte drinks don't increase your electrolyte levels for exercise and similarly, it has been shown that electrolyte levels are not decreased after or during exercise. But a naturally low electrolyte level even without exercise is possible.
So possibly a naturally/genetically low electrolyte level in your individual body could be an answer. But as has also been said, no one has all the answers to do with cramping and it is still a touchy subject.
Thank you
JJ