Hi folks, welcome to this video on the lactic acid system. Okay, so this is everything you need to know with regards to the lactic acid system, how it works, how it produces energy. Okay, so we're going to go through it nice and simple, nice and straightforward. Okay, what is the fuel of the lactic acid system? It's glucose, okay, which we get from glycogen.
Glycogen is just stored glucose. So glycogen is broken down into glucose and the glucose is then broken down and releases enough energy to resynthesize two molecules of ATP. Now when we break this glucose down, it's called glycolysis. that is the breaking down of glucose okay so glucose is broken down via glycolysis and i get energy for 2 atp okay which is good however i also get pyruvic acid also known as pyruvate okay now this is a very weak mild acid doesn't cause any problems the problems are going to occur now this is an anaerobic energy system okay there is no oxygen available and in the absence of oxygen this pyruvic acid is going to convert so lactic acid also known as lactate now that is a strong acid that is going to stimulate things like pain soreness and fatigue how is it going to cause fatigue it's going to inhibit enzymes It's going to stop enzymes like PFK from working, ATPase and Cpase from working. It's going to stop all them and that's why your performance starts to fall away when you use the lactic acid system.
So that's how it works. I've got glucose, one molecule of glucose from glycogen. I break it down via a process called glycolysis.
It releases energy for 2 ATP. I also produce pyruvic acid or pyruvate. as a result of breaking down glucose and when there is no oxygen available which there isn't in the lactic acid system that pyruvic or pyruvic converts to lactic acid or lactate and that creates pain soreness and fatigue okay what else do we need to know about this system it's good for one to two minutes some textbooks say two to three minutes that's fine i'll get you the max as well but you'll only be able to use this system for one to two minutes and it's not because of that running out Unless your diet is very, very poor.
You've got plenty of glucose and glycogen until last year. It's because of that. The pain, the soreness and the fatigue are going to stop you in your tracks after two minutes.
You are going to have to stop working. Okay? When is the only time you do use this system? When you are working at maximal intensity. Okay?
Once two minutes at maximal intensity, that is the prime time that you will be using your lactic acid system. So there's a picture of Alison Felix. She's a 400 meter runner.
She is someone who is going to use her lactic acid system a lot. She's going to use it after the first bend of her 400 meter race. It'll take her about 10 seconds to get to the first bend.
In that 10 seconds she'll use her ATP PC system. When that is exhausted after 10 seconds she'll then move into her lactic acid system and this will get her home. But obviously other athletes will use it.
800m runners, 1-200m swimmers, 200m runners are going to use their lactic acid system. If you're working maximally for longer than 10 seconds, you are going to use your lactic acid energy system. And what we've described there is the way that it works. The final thing I'll say on this is, you could get asked what are advantages and disadvantages.
this system okay well You've just got to look at what we've put up here to try and figure that out. Main advantages are that because it's anaerobic, it is quick energy production. We don't have to wait for oxygen to become available. So the energy production is very rapid.
So that's a definite advantage of the lactic acid system. Another advantage is that we can produce this rapid energy source for up to two minutes. Now that may not sound like a lot, but two minutes of energy production without oxygen.
That's very, very impressive. Okay? So that's another key advantage of the lactic acid system. What are the obvious disadvantages?
In the absence of this oxygen, pyruvic is going to turn into lactic or lactate, and that's going to create pain, soreness, and fatigue. Okay? The final key disadvantage is that when I break down one molecule of glucose, I am only getting 2 ATP. It may sound like not a bad relationship, one molecule of glucose, two ATP. That's actually not a lot.
If you watch the video on the aerobic system, you'll be able to see just how much energy you get from one molecule of glucose if you break it down thoroughly. So what we say there is there is a low energy yield from this system. You don't get much energy from that molecule of glucose. So it's well worth being aware of those advantages and disadvantages.