NSCF Certified Personal Trainer Practice Exam 2025 - Free Personal Trainer Practice Questions and Study Guide

Dehydration has a significant impact on training performance, primarily through its effects on blood plasma volume. When an individual becomes dehydrated, the volume of plasma in the blood decreases, which can lead to increased viscosity (thickness) of the blood. This thickened blood can impede circulation and reduce the efficiency of oxygen delivery to the working muscles.

As the body’s demand for oxygen increases during exercise, the heart compensates for reduced blood volume by increasing its rate of contraction to maintain adequate blood flow and oxygen delivery. This results in elevated heart rate values during training. Essentially, the heart works harder to meet the demands of physical activity, which can lead to quicker onset of fatigue and reduced overall performance over time.

In light of this, the assertion that dehydration leads to increased heart rate values is substantiated by the physiological changes that occur in the body during dehydration. Maintaining adequate hydration is crucial for optimal training performance and to minimize the cardiovascular strain caused by decreased blood plasma volume.