Glutamine is the most abundant amino acid in the body and central to supporting metabolic and other biological functions. It is nutritionally labeled non-essential; however, under situations where the body is under physical stress such as exercise, the body’s utilization of glutamine increases substantially. For example, intestinal and immune cells consume glutamine at high rates to support metabolism and cellular defenses. In addition, glutamine is used in the body to make antioxidants that defend us against oxidative stress molecules that can increase during intense exercise. Because glutamine becomes so important during physically stressful situations, it is now considered to be conditionally essential.
Why is glutamine important to the body during intense exercise?
1. Gut support
We will start in the intestines or gut. This tissue is semi-permeable to allow movement of fluids and nutrients from inside the gut into the body. However, under certain situations, larger molecules such as toxins can leak through the intestinal barrier into the body, which is termed intestinal permeability (sometimes call “leaky gut”). These toxins promote inflammation in the body. Intestinal permeability can occur during intense and long duration exercise and is exacerbated when exercise is performed in the heat. What’s happening is blood is diverted away from the gut to support exercising muscles and the blood is also circulated to skin surface to help with removing heat from your body. The reduced blood flow to the gut increases oxidative stress molecules that damage the intestinal wall.
Glutamine is an important nutrient for intestinal cells and evidence suggests that these cells prefer glutamine over glucose. Glutamine has numerous roles, including metabolic support, cellular growth, and namely, gut barrier stability. Data from our lab and others have demonstrated reduced intestinal permeability during intense exercise when glutamine is ingested before exercise bout. This indicates gut barrier protection during situations of physical stress. See figure below.
2. Glutamine and antioxidant defenses
Next, we will discuss how glutamine supports immune function during intense exercise. Like the gut, glutamine is an important nutrient for immune cells. Glutamine is use for metabolic activity and is essential for immune cell function. Specifically, glutamine can be used to generate compounds that neutrophils can use to defend against oxidative stress. It is also used to generate circulating antioxidants in the blood. We found elevated circulating levels of antioxidants among individuals who ingested glutamine before and after intense exercise. This demonstrates heightened protection against oxidative stress molecules that can rise during heavy exercise.
3. Glutamine supports hydration.
Lack of hydration that leads to dehydration during exercise can impair both physical and cognitive performance. It’s important that fluid consumed before, during, and after exercise is absorbed quickly from the intestines. Evidence suggests that glutamine added to a hydration formula stimulates water and sodium absorption from the small intestine. This accelerates the re-hydration effort.
Conclusion
In summary, glutamine becomes an essential nutrient during intense and long duration exercise and become especially important when exercise is performed in a hot environment. The reason is that glutamine supports gut stability, antioxidant defenses, and hydration. Zuul Hydration is formulated with glutamine to provide these benefits.
-Micah Zuhl, Ph.D.