Remember that sweat normally contains more or less a gram of sodium per liter - there's a lot of variability depending on the individual and their heat acclimation. If you're eating salty foods, then good, but if you're relying on gels and electrolyte supplements for your sodium, make sure you're getting enough. Ultima wild raspberry only contains 37.5 mg sodium per packet! If you took enough of those to replenish even an hour's worth of sweat, you'd be way overdosing on some of the other heavy metal minerals in it.