Drink 7-10 ounces (200-300 ml) every 10-20 minutes during exercise. For sessions longer than 60 minutes, add electrolytes. Weigh yourself before and after exercise — drink 16-24 ounces for every pound lost to fully rehydrate.

For exercise under 60 minutes, water is sufficient. For longer sessions or intense exercise in heat, sports drinks help by replacing electrolytes (sodium, potassium) and providing carbohydrates for energy. Choose drinks with 6-8% carbohydrate concentration.

Even 2% dehydration can reduce endurance, strength, and cognitive function. At 3-4% loss, performance drops significantly and heat-related illness risk increases. Pre-hydrating 2-3 hours before exercise and monitoring urine color (pale yellow is ideal) helps prevent performance decline.