To understand what lactic acid actually is, we recommend using a runner as an example. You wake up, put on your running shoes and hit the road. What happens after that?
Let’s say you are healthy and have an average fitness level. Your muscles would’ve stored up a sufficient amount of carbohydrates (in the form of glycogen) from your dinner the previous night. As soon as you start your running session, your muscles will start breaking down the glycogen into smaller energy units called glucose.
Your cells will break down the glucose down further and convert it into pyruvate and lactate. When you exercise at a moderate level, you will breathe in enough oxygen and exhale carbon dioxide so that the pyruvate will enter the compartments of the muscle cells. These cells are called the mitochondria, which is where ATP – energy – is formed.
Your cells will continuously seek equilibrium
This is why there will always be some lactate being produced. When you start exercising, there is more pyruvate than lactate. So as you increase your exercise intensity, your muscles demand more energy. Ten minutes into your run the energy compartments in your muscles will begin to reach maximum capacity in terms of much pyruvate they can take up and turn over into ATP. Here is where the lactate comes in. When the mitochondria can no longer take up pyruvate, they will start to produce more lactate to compensate. Lactate levels increase as performance drops off.
Lactate doesn’t only appear when you’re training hard
Muscles use lactate for energy during moderate and intensive exercise. As your fitness improves, your muscles wiil start to create more mitochondria. When this happens you’ll be able to take up up even more lactate and use it for energy. After a few months of a cardio routine, your blood lactate levels will actually decrease for a given exercise intensity, which means that you’ll be taking up lactate more efficiently.
Are you interested in learning more about how the human body responds to exercise? Do you want to discover the science behind exercise? Then Trifocus Fitness Academy’s Comprehensive Exercise Science Certification is for you. Follow this link to find out more.