How much fluid should an athlete aim to replace about 2 hours before exercise and during exercise to prevent dehydration?

• A. About 2–3 ml/kg 2 hours before; 100–150 ml every 30 minutes during exercise
• B. About 4–6 ml/kg 2 hours before; 100–150 ml every 2 minutes during exercise
• C. About 3–4 ml/kg 2 hours before; 100–120 ml every 20 minutes
• D. About 5–7 ml/kg 2 hours before; during exercise, 150–250 ml every 15–20 minutes

Answer: (D)

Hydration strategy is about starting well-hydrated and then replacing fluids at a rate that matches losses during activity. About two hours before exercise, aim for roughly 5–7 ml of fluid per kilogram of body weight. This amount helps ensure the body is well hydrated at the start and reduces the risk of thirst or GI discomfort once you begin moving. For a typical athlete, that’s several hundred milliliters, enough time for absorption before the workout.

During exercise, target about 150–250 ml of fluid every 15–20 minutes. This cadence helps offset sweat losses and maintains fluid balance without overloading the stomach, which can cause nausea or bloating. Depending on how much you sweat and the environment, you may adjust upward or downward, but this range provides a practical balance for many athletes.

In short, start with a solid pre-exercise drink plan (5–7 ml/kg two hours before) and maintain a steady intake during activity (150–250 ml every 15–20 minutes) to help prevent dehydration.