special subjects
Overview of Exercise
Hydration
 Thirst is not an accurate indicator of fluid requirements. Drinking when feeling slightly or moderately parched but before feeling extremely thirsty helps maintain proper hydration and avoid electrolyte imbalance, illness, and possible seizures and/or death (eg, from Hyponatremia due to excess consumption of free water). Avoid overhydration during exercise because it can cause hyponatremia sometimes severe enough to cause seizures. 8% (8 g/100 mL, or 20 g in a typical 250-mL serving) decrease gastric emptying and slow fluid absorption. Mixing plain water with sports drinks at a 50:50 ratio allows faster absorption of the glucose and electrolytes. Patients with findings suggesting Overview of Heat Illness or 