So I'm recently getting back into running, but I've been having problems with cramping in my calf muscles (which is sometimes bad enough to force me to stop running). And then today when I was driving my calf muscles cramped badly enough that I had to pull over. My sodium and potassium levels have been low for a while now, and in the last blood tests I had, my sodium level was 135mmol/l (ref range 136-148mmol/l) and potassium was 3.2mmol/l (ref range 3.8mmol/l-5.0mmol/l). My GP was unconcerned with each of these results because I was asymptomatic. However, I am a little worried because I tend to worry about these things and I'm now wondering about the cramping and the electrolytes and whether they could be linked. So I was wondering, does anyone have any experience with low sodium and low potassium? And has anyone had cramps as a symptom? If you did have this electrolyte imbalance, were further tests performed or was your doctor unconcerned? And has anybody else dealt with recurrent muscle cramps? If so, what did you do? I'm not overly concerned, just interested really. It would be good to know for sure that this really isn't a problem. I have an appointment with my GP on Tuesday, and I will discuss the cramping. Just looking for some reassurance until then.