Citric Acid Cycle (Krebs Cycle)

Definition

Series of mitochondrial chemical reactions oxidizing energy substrates to generate ATP and energy cofactors (NADH, FADH2). It is the central pathway of aerobic catabolism.

How it works

The citric acid cycle, also known as the Krebs cycle or tricarboxylic acid cycle, is a succession of 8 chemical reactions that occur in the mitochondria. It oxidizes acetyl-CoA (derived from all macronutrients) and generates reduced cofactors (NADH, FADH2) used to produce ATP in the electron transport chain. The Krebs cycle is the metabolic convergence where glucose, lipids, and proteins are oxidized to produce energy. Its efficiency is fundamental for physical endurance and metabolic health.

Role

Oxidizes energy substrates and generates cofactors for ATP production.

Examples

• Oxidation of pyruvate from carbohydrates
• Oxidation of acetyl-CoA from fatty acids
• Production of NADH and FADH2 for ATP
• Intermediates for biological compound synthesis

Recommendations

Perform aerobic training to optimize the functioning of the citric acid cycle. Ensure a balanced energy intake of macronutrients. Maintain good mitochondrial health through physical activity and an antioxidant-rich diet.

Key takeaway

The citric acid cycle is the central pathway of aerobic energy production for all macronutrients.

Related terms