I have, for many years of my life, been bothered by recurring nocturnal calf cramps. For those not familiar with the condition, they are a very strong and painful cramping of the calf muscle occurring during sleep or when waking, with muscle soreness not infrequently remaining after the cramp had ended.

Only in the last few years did I seriously consider taking steps to address the problem and to track both my calf cramps and the steps I was taking to alleviate them. In the past I had made changes in my diet and in my exercise regimen, but never tracked their effect (if any) on calf cramping. Improving my diet and engaging in some sort of exercise (including some stretching)  seemed to improve things (based on my recall), but I had no data to support my impression.

Off and on, starting in 2008, I began to track my nocturnal calf cramps. Starting in early May and ending in late October, I recorded six cramps in that six month period:

I really don’t know how to account for the gaps between incidents or for the grouping in September. Looking back at the records I did keep, I don’t see any major changes that would account for it. Or what would account for the four month period where I experienced no cramps at all. I think this underscores the need to keep accurate and consistent records when tracking something like this.

In 2009 I again starting tracking at the beginning of February through to the end of August. I recorded three cramps during that eight month period:

Again I have no real explanation for the frequency or for the gaps. Three in eight months this time versus six in six months the previous time. This is a pretty significant decrease in frequency, without apparent reason, including an almost three month cramp free period.

I started tracking again on October 15th of 2009. To the end of 2009 I experienced no cramping (and this was in the absence of any particular treatment). This time I started tracking continuously to the present, but I did not continuously track supplementation (I had on and off supplemented with Magnesium Citrate, 200-400 mg per day).

From late 2009 to mid 2010 I experienced eight cramps as follows:

Again there are large gaps and a grouping of five cramping episodes in late May and early June with no readily apparent explanation.

On June 7th 2010 I began regular daily supplementation with 200mg of Magnesium Citrate (brand: Now Foods, if that’s important). In the period following I experienced cramping on:

Starting September 11th 2010 I also began supplementation with Potassium Citrate, approximately 400mg (4 x 99mg to be exact), taken in the evening along with the Magnesium Citrate (the Potassium Citrate was also from Now Foods).

Reasoning behind the supplementation: magnesium supposedly aids muscle relaxation. Potassium is involved in electrical signaling (potentiality) of muscle movements (activation).

The Dietary Reference Intakes for these two minerals for an adult male (31+) are currently:

  • Magnesium: 420 mg
  • Potassium: 4700 mg

From the above figures it can be seen that my magnesium supplementation was a fairly high percentage of the DRI (just under 50%) while my potassium supplementation was a relatively small percentage of the DRI (less than 10%).

After September 11th 2010 (with the combined magnesium and potassium supplementation) I only experienced one very minor (not really painful) calf cramp on December 8th 2010 – which actually occurred after waking, but while still in bed. I’m not sure I should even count this as an event, since it isn’t something that woke me as had occurred previously. So essentially there were no further nocturnal calf cramps from mid-September 2010.

During this time I also added a couple of activities to my exercise regimen. Starting in August 2010 I started playing badminton again (something I hadn’t done since childhood) and in November 2010 I also started taking ballet classes (something I had never done before). Possible importance: the ballet involved a lot of work using and stretching the legs (especially the lower leg). Badminton also involved a lot of movement, though less specific than ballet.

Starting January 1st 2011 I discontinued the magnesium supplementation. My reasoning was that I had still experienced nocturnal calf cramps after beginning magnesium supplementation. Perhaps just potassium alone would be sufficient, since I had experienced no further significant cramping episodes after adding the potassium (of course there’s the possibility that there was a synergistic relationship between the two – eliminating one would hopefully reveal whether that was true or not).

Since January 1st 2011 there have been no re-occurrences (3+ months now). Successful so far, but given that I also made some changes to my activity regimen since September 2010 I am left wondering if the change might have been due to that rather than to the supplementation. I think this highlights the difficulty of ascribing an observed change to a single variable, since as evidenced by my previous data collection efforts there had been other significant periods of time where I had not experienced any cramps (periods of up to three  months) for no readily apparent reason.

So starting April 1st 2011 I also discontinued the potassium supplementation (so now I am not taking any supplements at all – not for this or for anything else). I will continue to track any nocturnal calf cramps. There have been none so far.

This is something that will have to be an ongoing project for me. The data I have gathered so far have been very helpful to me and I feel I have learned from what I have done so far, but I don’t feel that I can draw a definitive conclusion. The potassium supplementation would seem to have been helpful, but further tracking and experimentation will tell me more. This is an ongoing project for me. Perhaps just a decent diet and the appropriate physical activity will suffice.

The aspect of potassium supplementation that concerns me is that the amount I supplemented with was not really very large in terms of the daily requirements. Looking at the USDA nutrient database for food equivalents of my supplementation I found the following:

  • 200 grams of baked potato contains around 1,000 mg of potassium
  • 220 grams of duck contains around 550 mg of potassium

Other good sources are tomatoes and beans.

So it would not be difficult to get the amount of potassium I was supplementing with from food sources without having to radically alter my diet. My current plan is to complete a three month period (April through to the end of June) with no supplementation and see my results.

Thoughts: My efforts so far have made apparent to me the difficulty in tracking and in thinking of all the relevant variables that might be responsible. It’s convenient to think that there might be a single controllable, measurable variable to account for things, but I’m really not sure that this is the case. I did some research and the medical literature does not reveal a documented cure for this condition, though it is generally theorized to be a result of an electrical/electrolyte imbalance, hence the potential importance of potassium intake and supplementation. I used Potassium Citrate in my experiments, though other forms exist. The citrate is readily available and inexpensive. Potassium Chloride is also readily available, but contains chlorine is also an electrolyte (so it can effect muscle function).Then I would be in the position of not knowing whether the observed effect was a result of the potassium or chlorine.