What role does glutamine play during prolonged exercise?

Glutamine plays a significant role during prolonged exercise primarily as a precursor for gluconeogenesis. During extended periods of physical activity, the body may deplete its glycogen stores, which can lead to a reliance on other sources for energy. Gluconeogenesis is the metabolic pathway through which glucose is synthesized from non-carbohydrate sources, and glutamine can serve as one of those sources. It can be converted into glucose in the liver and kidneys, facilitating energy production when carbohydrate stores are low.

Additionally, glutamine helps regulate acid-base balance in the body and supports the maintenance of muscle protein synthesis and immune function, particularly important during periods of stress such as prolonged exercise. While glutamine may influence various biochemical processes related to recovery and performance, its role in gluconeogenesis is particularly crucial during sustained physical exertion.