Performance begins to be impacted when fluid loss exceeds which percentage of total body mass?

When fluid loss exceeds 2% of total body mass, performance begins to be adversely affected. This is due to the body's reliance on proper hydration for optimal physiological functioning, including thermoregulation, cardiovascular stability, and muscle function. Fluid loss leads to a decrease in blood volume, which can impair oxygen delivery to muscles and hinder overall athletic performance.

At this initial threshold of 2% dehydration, individuals may start to experience symptoms such as fatigue, decreased coordination, and a decline in physical endurance. This is critical for athletes and active individuals to monitor, as staying hydrated is essential for maintaining peak performance levels. Beyond this point, as fluid loss increases, the negative effects on performance become more pronounced, underscoring the importance of preventive hydration strategies.