I'm doing a 4 hour ride tomorrow in the warmest temperatures of the year so far. I sweat A LOT so I picked up a box of Electromix by Emergen-C to replace electrolytes during the ride. I was surprised to see that this product, marketed as a sports drink mix, doesn't have a lick of sodium in it. They kind of elude to the lack of sodium by stating that "modern diets typically contain excessive sodium". I don't think that excess salt in the diet ensures that we'll have adequate sodium left in our bodies after sweating for hours, though.

Guess I'll drop a little pinch of sea salt in my bottle each time I refill.