Reflection #2: Gluconeogenesis

One aspect of gluconeogenesis that really stuck with me was how the body can essentially “rewind” metabolism to make glucose from non-carbohydrate sources. I never realized how crucial this pathway is, especially during fasting or intense exercise. I really enjoy running, and learning about gluconeogenesis actually helped me understand why certain long runs feel so different depending on when and what I eat beforehand. For example, on mornings when I run without breakfast, I’ve noticed a kind of slow-burn fatigue that’s different from just being tired. After studying this pathway, it finally made sense: my liver is converting lactate, amino acids, and even glycerol into glucose to keep my blood sugar stable. It’s not just that I’m “low on carbs” but that my body is literally performing a metabolically expensive process to keep me moving. What I found most surprising is how tightly regulated the processes of gluconeogenesis and glycolysis are and how closely related they are than I anticipated. The idea that the body balances these two opposing pathways through hormones like insulin and glucagon is so elegant. Understanding that balance actually changed how I think about nutrition, and I’m more aware now of why timing and composition of meals matter for performance and recovery.