AFAA Personal Trainer Certification Practice Exam 2025 - Free Personal Trainer Practice Questions and Study Guide

The primary function of glucose in the body is indeed as the body's usable form of carbohydrate. Glucose serves as the main source of energy for cells and is crucial for various bodily functions. When carbohydrates are consumed, they are broken down into glucose, which enters the bloodstream and is transported to cells throughout the body.

Cells utilize glucose in various metabolic processes to produce ATP (adenosine triphosphate), which is the energy currency of the cell. This energy is vital for muscle contraction, brain function, and overall metabolic activities. The body's reliance on glucose as a quick and efficient energy source is essential for maintaining homeostasis and supporting exercise performance.

While glucose can be stored as glycogen for later use, its immediate role is as a readily available energy source, making it the primary carbohydrate utilized by the body. The other options, such as energy storage, protein synthesis, and fat metabolism, represent different metabolic processes and functions but do not capture the direct role of glucose as a usable form of carbohydrate in energy production.