Sweat rates and sweat sodium concentrations in athletes

Study of sweat rate and sweat sodium loss in professional NFL players (44 members of the Philadelphia Eagles), illustrating the wide between-person variability: sweat sodium concentration ranged from roughly 345 to 2,277 mg per litre (15 to 99 mEq/L in the paper’s own units). This variability is why blanket electrolyte advice is unreliable and why heavy, salty sweaters in long, hot efforts are the group with a real case for supplementation. Moderate.