Hydration & Electrolytes

Even 2% body-mass fluid loss impairs cognitive performance and endurance, and chronic underhydration is associated with higher serum sodium and increased long-term risk of chronic disease in large cohort analyses. In the Gulf climate, sweat losses raise electrolyte as well as water needs — plain water alone can dilute sodium in heavy sweaters. Practical targets are pale-yellow urine, 30–35 ml per kg of bodyweight daily as a baseline, and added sodium and potassium around prolonged heat or training exposure. Note that dehydration falsely elevates hematocrit, hemoglobin, and creatinine on a blood panel, so hydrate normally before testing.