Question: I keep reading that, for vegan athletes, sodium is so important they will benefit from sea salt or other sodium supplements during hard training or during any hard event, and if they don't get this extra sodium, they risk getting muscle cramps. Is any of this true or only misinformation? Does hard training or demanding events require additional sodium? And, are muscle cramps caused by lack of enough sodium?
Answer: It is misinformation. If you are on a high sodium diet, you will excrete a lot of sodium in your urine and sweat and have a need for more of it under times of stress, such as a marathon. If you are accustomed to a low sodium diet, your kidney and skin will not excrete lots of sodium, and supplementation during heavy and prolonged exersicse will not be necessary.