That pain you feel after an arduous exercise session is due to lactic acid. Our fuel is carbohydrates.
Muscle cells metabolize carbohydrates to convert them into adenosine triphosphate (ATP), the energy that allows them to contract to generate movement. This process creates waste: lactic acid.
With a moderate intensity aerobic exercise, the cells do not generate too much lactate and there is still room for them to get enough oxygen to continue the activity.
Also: WHAT IS LACTIC ACID?
And if we extreme the requirement and try, for example, to do a sprint for 400 meters?
At the beginning we will run without problem, but in the end we will notice that our body is blocked. The cells are metabolizing hydrates at full speed to produce the necessary energy, and that generates a lot of lactate that remains a few seconds inside the cell, which steals a valuable space to oxygen, which is left out.
The cell cannot work without oxygen and the muscles are blocked, which produces the abrupt exhaustion that prevents us from performing.
But when we continue with intensity an exercise, lactic acid will begin to accumulate by not giving the body time to remove it. This causes acidification of muscle fibers, which has two important consequences:
- Enzymes responsible for breaking the glucose molecule to obtain energy are inhibited, so the energy grind of this path is cut off and as we know, if there is no energy, there is no movement.
- It prevents calcium from joining the muscle fibers and consequently from contraction.