Which of the following is NOT a measure to prevent seasickness?

Conducting physical exercise is not typically regarded as a preventive measure against seasickness. Seasickness, or motion sickness, often arises from a conflict between the body's sensory systems—what the eyes see and what the inner ear senses. When you are on a boat, particularly in rough conditions, physical activity can exacerbate this conflict by adding additional motion that might confuse the body further and can make symptoms worse.

On the other hand, staying hydrated, medicating with seasickness tablets, and ensuring adequate sleep are all strategies recognized for their effectiveness in preventing or mitigating the symptoms of seasickness. Maintaining hydration helps the body function properly, which can alleviate the effects of seasickness; medication can target and reduce symptoms effectively; and ample sleep provides the body with the restorative time it needs to cope with the stresses of being on the water. Each of these measures serves to stabilize the body’s internal systems and enhance overall well-being while at sea.