What preventive measure could the student have taken to avoid becoming hyponatremic?

Drinking an isotonic sports drink instead of plain water would have provided the student with electrolytes, particularly sodium, which are essential for maintaining proper fluid balance in the body. During intense physical activity, the body loses not only water through sweat but also electrolytes like sodium. If the student consumed only water in large quantities without replacing these lost electrolytes, it could lead to dilution of sodium levels in the blood, resulting in hyponatremia. An isotonic sports drink contains a balance of fluids and electrolytes that can help prevent this condition by replenishing both the water and necessary salts lost during exercise.

Understanding the role of electrolytes in hydration is crucial, especially in athletic contexts where fluid loss is significant. Therefore, opting for an isotonic drink would have been an effective preventive measure against becoming hyponatremic.