Lactic Acid - GCSE Biology Definition

Lactic acid is a substance produced in the muscles during anaerobic respiration, which happens when the body breaks down carbohydrates for energy without using oxygen. This is a process called anaerobic respiration and often occurs during intense exercise. While it helps provide energy quickly, the build-up of lactic acid in the muscles can cause a burning sensation and make them feel tired or sore. This is why we often feel muscle fatigue after hard exercise. The body eventually removes lactic acid and recovers, especially when we rest or continue with light activities allowing oxygen to help break it down. Understanding lactic acid is important in GCSE Biology as it helps explain how our bodies respond to physical activity and manage energy.