It used to be said that getting a sports massage will help to flush out your 'lactic acid build up' in your muscles”.
Well, I am here to tell you that, this statement should have left our mouths years ago and in fact, everyone should all think of lactic acid as our ‘back up’ fuel source.
If we look at basic physiology, massage is unable to squeeze out the lactic acid from our muscles because lactic acid is recycled within our bodies as part of an important energy process called glycolysis.
Let’s look at an example. Say you raced your friend to the car.
Due to the speed you run, your muscles would be screaming out for oxygen to help keep up with the energy demand, but because your body could not get enough oxygen in – lactic acid was produced.
Where does lactic acid come from?
On a cellular level, there is a process called glycolysis, which helps to convert glucose into energy. Glucose will turn into pyruvate acid. If no oxygen is available pyruvate acid ferments and converts to lactic acid - called anaerobic metabolism. This lactic acid is your ‘back up’ fuel system. When you first start to sprint within 6 seconds, any energy stored in the muscle depletes, a 10 seconds window where muscle will use any available creatine to make energy and then around 30-40 seconds glucose stored in the muscles will be broken down into pyruvate and due to the lack of oxygen, it will undergo fermentation and be converted into lactic acid which will provide you with a couple of minutes more of energy to get you there quicker than your friend.
When the sprint ended and you go to the car, you would have found your body trying to get as much oxygen in as possible - this is called EPOC - Excess Postexercise oxygen consumption - aka I NEED OXYGEN! Once the oxygen becomes replenished in your muscles, your breathing rate slows down and then repayment begins.
What happens to lactic acid?
Any lactic acid circulating in the blood which was not used for energy is readily then converted back to pyruvate acid in the muscles and enter the pay as you go system - the aerobic pathway, where tonnes of energy is produced for body function. Even typing this I am using this pathway.
You can now see that lactic acid does not linger in our muscles and that in fact it gets recycled back into pyruvate to enter the aerobic pathway where there is plenty of oxygen or the liver may convert it back to be stored as glycogen, only to be release if blood sugar levels are low.