What type of acid in our blood cause us fatigue during exercise?

Answer 1

Hi there,
During any form of physical exercise, the Mitochondria in our cells respires. When this is completed in the full presence of Oxygen, AEROBIC respiration takes place, which as a very short summary produces Pyruvate which is then used to make energy.

However, when oxygen is low or not present - i.e, the demand for oxygen is more than we can actually breath in and get around our body before being used up, a less efficent product is made - Lactate or Lactic Acid. This is the molecule that causes fatigue, as our muscles work at an Optimum pH - this acidity causes that pH to change, as a result the biochemical reactions slow down or cannot take place. This process is ANEROBIC respiration.

This Lactic Acid causes an 'Oxygen Debt' which is eventually broken down to form Pyruvate again - and the full store of energy is released.

If you want more detailed information on this - such as the ETC etc etc

Tom
Biologist

Answer 2

I wouldn't say it causes us fatigue. High levels of CO2 in our blood can react with H20 to form carbonic acid (H2CO3) which then dissociates and gives off an H+ and a bicarbonate ion (HCO3). The H+ in the blood makes it acidic, which in turn makes hemoglobin lose affinity for oxygen thereby releasing the oxygen into the body's cells. This causes an increase in respiration, so you'll breathe more rapidly.

The build-up of lactic acid in the muscle tissues occurs when the tissue is not receiving enough oxygen so the cells must resort to anaerobic respiration for energy, and a waste product of anaerobic respiration is lactic acid. That is what causes the burn in your muscles, but it doesn't make you fatigued necessarily.

The only thing that would make you tired during exercise is if your brain is not getting enough oxygen, which isn't caused by acid in the blood really.

Answer 3

You'll be told, and should answer, lactic acid, though it looks like something else is happening.

The original experiment was good, but too correlational. It seems that it may have been the old correlation/causation error.

That is only prelim though! It is interesting to think about, but just say lactic acid!

Answer 4

lactic acid.when u overdo Ur exercise our muscles are depleted of our oxygen.so it shifts to anaerobic respiration(it uses carbon di oxide for respiration).as a result a byproduct of lactic acid is formed.this causes fatigue.even if our reserve glycogen is depleted muscle fatigue is caused.

Answer 5

Lactic acid.

Answer 6

lactic acid in your muscles, carbonic acid is in your blood causing changes in respiration

Answer 7

lactic acid is the culprit