National Council for Certified Personal Trainers (NCCPT) Practice Test

The primary purpose of glycogen stored in the liver is to supply energy. Glycogen serves as a critical energy reserve for the body, especially during periods of fasting or intensive physical activity. When the body requires glucose for energy, such as between meals or during exercise, the liver converts glycogen back into glucose and releases it into the bloodstream. This process helps maintain blood glucose levels within a normal range, ensuring that vital organs, particularly the brain, have a readily available energy source.

While other functions are vital for overall health, such as temperature regulation, muscle recovery, and immune function, they are not the primary roles of liver glycogen. Instead, those processes rely on various nutrients and systems in the body, rather than being directly linked to the function of glycogen stored in the liver. Therefore, the correct response highlights the essential role of glycogen in energy supply, which is crucial for maintaining overall metabolic homeostasis and supporting physical performance.