When does an individual typically begin to feel thirsty during exercise?

The feeling of thirst during exercise is commonly triggered based on physiological responses to dehydration. As the body begins to lose fluids and experiences a decrease in body weight, particularly due to sweat loss, the onset of thirst occurs. Typically, this sensation can initiate when body weight drops by 1-2%. This early indication is crucial for maintaining hydration levels and preventing further fluid loss, which can adversely affect performance and health.

The thresholds of 3-4% weight loss represent more severe dehydration, at which point an individual may experience more intense symptoms and potential performance deficits. However, the initial urge to drink water and the body's thirst mechanism generally kick in at the lower threshold of 1-2%. This proactive response helps ensure that proper hydration is maintained during physical activity.