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11 Feb 2004

Cramps while swimming
Hi there.
I have recently taken up swimming. I started with very few laps and have built up to a maximum of 80 laps. But after about 50 laps I start to get cramps in my feet. Then I have to stop every second lap or so to get the cramp out. Please can you give me some advice as to what might be wrong.
Answer 408 views

01 Jan 0001

HI Mike

Cramps during swimming are actually very common and there is a good physiological reason for it too, as I'll explain. There are so many myths about cramping that a lot of what I have to say may come as a surprise to you. To start with, the bottom line is that cramping is not caused by mineral deficiency and so supplements do not help prevent them (at least not directly, although they may contribute indirectly, as I'll explain). A few years ago, a big study on 2 Oceans and Comrades runners found that when you compare the magnesium, sodium and calcium levels of runners with cramp with runners without cramp, there's no difference - that means that people cramp even though their mineral levels are exactly the same. So, this myth has come about based on very early studies in mines etc. and a lot of it has been driven by sports drink companies who want to market the products as a cure for cramp.The bottom line is that you are cramping even though your vitamins and mineral levels are normal.

So, then, what causes cramp? Without getting too technical, cramping is caused by a reflex stimulation of the muscle by the central nervous system - the muscle is constantly controlled by nerves and reflexes, and there's good evidence to show that a cramp occurs when the reflex control of muscle breaks down and the muscle is stimulated excessively. Exactly what causes this is unknown although it is known that fatigue is a major contributor - that's why people cramp late in races and training sessions, more often they also cramp in the heat (it causes more fatigue), or when it's windy, a hilly course, or a tough race in the case of running and cycling. It also explains why you cramp in the muscles you use only for cycling and not in the arms, for example - the muscles become fatigues, and this somehow interferes with the nervous system and the control of the muscle, causing them to cramp. NOw, for swimming, which is your particular case, the cramp is so likely to happen because your toes are pointed away from pretty much all the time - what this does is put the calf muscle into a shortened position, and this affects the reflex control that is responsible for relaxing the muscle. In other words, the reflexes work better when the muscle is stretched, and swimming puts the muscle in a very vulnerable position. COmbine this with some fatigue, and you have a cramp.

So, the immediate treatment for a cramp is to stop and stretch the muscle very well - tests have shown that as soon as you do this, the reflex control of the muscle is restored, and this stops the cramp immediately. In terms of prevention, stretching regularly to improve your overall flexibility may help

Then the other factor that helps prevent cramp is muscle strength. It's not a co-incidence that the people who cramp are often racing hard, or pushing harder than their training has allowed them. So, the training is very important, and getting to maximum fitness is vital. In your case, it sounds like you have really built up from very few, and now you are doing 80, and so maybe what you can do is just to reduce the distance every second day - there's probably not much to be gained from cramping every day - maybe do 60 laps and see how that goes - you might just be able to reach that. Otherwise, break the 80 laps down into 8 groups of 10 and then swim the 10 laps much harder, and then take a good 3 minute rest, before repeating this. All this will help you get stronger, and by improving the muscle strength, you will delay muscle fatigue, and then hopefully the cramp won't occur.

So, these are the natural, more scientifically ways of preventing cramp.

I hope they work for you.
The information provided does not constitute a diagnosis of your condition. You should consult a medical practitioner or other appropriate health care professional for a physical examination, diagnosis and formal advice. Health24 and the expert accept no responsibility or liability for any damage or personal harm you may suffer resulting from making use of this content.
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