Understanding Energy Systems in Exercise

Hey what's up guys, Matt with Movement System. In this video we're going to talk about the energy systems involved in exercise. So we're going to talk about the four or five different energy systems. We're going to talk about the ATP-PC cycle, we're going to talk about aerobic slash anaerobic glycolysis, the Krebs cycle, oxidative phosphorylation, and the metabolism of fats. We're not going to go over the details of any one energy system, but we're rather going to focus on how we actually use these energy systems during exercise. If we're doing weightlifting, interval training, endurance running, How are we actually shifting the utilization from one system to the other system and how are we actually getting training adaptations in these energy systems? Let's go ahead and dive into it. Alright, so we're going to start off by pulling this chart from page 54 of the Essentials of Strength Training and Conditioning book. And this chart is going to show us relatively which energy system is going to be providing the most energy during short bouts of high intensity effort versus during long bouts of low intensity efforts. Alright, so importantly, this chart isn't showing us the number of ATP that are produced. Rather, this chart is showing us in column 1 the rate of ATP production from one system to the next. And basically... which system is the fastest all the way down to which system is the slowest. And then exactly inverse to this, we're going to see the capacity for total ATP production in that second column. Again, this isn't the number of ATP produced, but rather this is the energy system that's going to be producing the most versus the least total amount of ATP. So let's just go one by one. The ATP PC system here is going to produce ATP at the fastest rate. So this means that we're going to get ATP almost instantly. Within the first one, two seconds of exercise, we're going to be starting to produce ATP by splitting phosphocreatine molecules and basically giving that phosphate to an ADP to reform ATP. That happens right in the muscle very quickly and it can provide us with immediate energy. But the downside of this system is that it depletes the fastest, meaning it runs out and we can't use this system for very long. I actually have a whole video on the ATP PC system, which I'll link down in the description below if you want more details about it. But just know that this is our fastest system, but it produces the least amount of ATP total. All right, moving down to fast glycolysis, and you may have also heard of this as anaerobic glycolysis. This system is going to be the next in line. It's going to produce two net ATP per glucose molecule. And again, I have a full video that breaks this system down, but we're just going to focus on the big picture here. This system is going to produce two net ATP. So it's going to give you a little bit more than the ATP PC system, which actually only produced one ATP, but it's going to take a little bit longer. That said, it is also going to give you a little bit more total. So it's going to be that next system down. And the end product of fast glycolysis is going from glucose. So a glucose molecule being like a blood sugar molecule, breaking that down into pyruvate and then down into lactate. So that is the... the system of fast or anaerobic glycolysis and it's going to give us those two net ATP as well as produce some high energy substrates which can then be metabolized later. So some examples for these fast systems for the example of a shot put for example when we're putting a shot and it's just one quick effort that's primarily going to rely on the ATP PC system. A secondary contributor is probably going to be fast glycolysis but that's pretty much what we're using from an energy system perspective for that exercise of shot put. And then here we'll start to reference this chart which will make it a little bit easier to understand the trade-offs or the mixed cases. So for the example of a 100 meter sprint if we're doing that in 11-12 seconds what you can see here is there's going to be a mixture of systems. So the primary system this 11-12 second range is going to be anaerobic or fast glycolysis. But as you can see, there's some contribution from the ATP PC system that you see at the front of that chart, and there's some contribution from aerobic, but the primary system is that anaerobic glycolysis. So what this means, and this is oversimplified, but if it takes 100 ATP to run a 100 meter run, and again, that's very oversimplified, it takes thousands of ATP molecules, but let's just say it takes 100 ATP. This means that anaerobic glycolysis... might be giving you 50 or 60 of those ATP. The ATP PC system might be contributing 30 of that 100, and then maybe we're getting a contribution of 10 or 20 from the aerobic system. So as you can see, the 50 or 60% of our energy that's coming from the anaerobic glycolysis or the fast glycolysis process makes it the primary energy system. Now, that doesn't mean that the... Other systems are turned off, but rather they're just secondary contributors to the energy production that you need for this duration of an event. So any high intensity effort that's taking that 10 to 12 seconds, whether that be pole vaulting, whether that be a 100 meter run, a sprint or a breakaway in hockey, a run to first base in baseball, any of these types of plays that are taking about that 10, 15 seconds are going to primarily use that anaerobic glycolysis system. Alright, so getting back to the chart, we're going to talk about aerobic or slow glycolysis. And that's going to be kind of right in the middle. So for this energy system, we're getting a moderate amount of ATP and we have a moderate capacity for the system. Meaning that it can produce a fair amount of ATP, but it also takes a fair amount of time. So just to be clear, slow glycolysis is referring to breaking down glucose into pyruvates and then sending it into the Krebs cycle and into oxidative phosphorylation to be fully oxidized. If that pyruvate was turned into lactate, that would be fast glycolysis or anaerobic glycolysis. And in this 30 to 90 second range, we're going to use a mixture of both. If this video has been helpful for you so far, go ahead and smash that like button and subscribe so you don't miss any future videos. And also, make sure after you're done with this one, you check out all the videos in the description below if you want to learn more about one specific energy system. Alright, moving down the chart, we're going to talk about oxidation of carbohydrates. And this is a pretty broad term for saying... Krebs cycle and oxidative phosphorylation. Those are really the processes that are occurring in the mitochondria where we're actually breaking down acetyl-CoA into CO2 and creating these high energy substrates which will then lead to the production of ATP. So the full oxidation of carbohydrate or the full oxidation of glucose involves going all the way from a glucose molecule to pyruvate. through the Krebs cycle, through oxidative phosphorylation. And if we have the oxygen to go through all those steps and fully oxidize the glucose, we'll get to a total of 38 net ATP. So that's really what we're going to be talking about here in that fourth column, the full oxidation of carbohydrates. And again, that's requiring oxygen, but it's referring to the breakdown of glucose. And in that case, it's going to be the fourth in terms of speed of energy production. We need to have oxygen. We need to shuttle to the mitochondria. That takes time, but it's going to get a significant amount more ATP because again, breaking down one glucose molecule gets you all the way to 38 net ATP if you can oxidize the whole thing all the way through. Whereas if you're just doing glycolysis and you're ending at lactate, you're really only getting two net ATP. So the amount is much greater than 38, but the rate is actually much less because it takes more time to fully oxidize than it does to just turn it right into lactate quick. This is going to be the primary energy system for most distance events anywhere from running 800 meters ish to uh multiple miles 10 20 miles. We're primarily going to be relying on this system. As we get to really long events like a marathon we may get into the point where we're 50 50 between aerobic metabolism of carbohydrates and metabolism of fats and proteins primarily fats but it really takes long events to get to that point. For most endurance athletes we're going to be primarily using this carbohydrate metabolism and then that leads us into that final system oxidation of fats this is lipolysis and beta oxidation and i have a video that breaks this down as well but if we have a triglyceride which is a glycerol with three fatty acid chains we could first break the glycerol backbone off the fatty acids that's lipolysis and then we could chop up those fatty acids and that would be beta oxidation and those get chopped up into acetyl-coa which is then oxidized. So that whole process of breaking down triglycerides and breaking down fats all the way down to acetyl-CoA and then oxidation, it gets you a ton of ATP, 200 plus ATP actually, but it takes a lot of time to actually do that full process. A lot of oxygen is required. So this is really just a secondary system at most distances. If you're running a 5k, a 10k. This may give you 30% of your energy, 35, 40% of your energy, again, depending on your training status. But it really doesn't become a primary energy system until those really long duration events. If you guys still have any questions about energy systems, feel free to drop them in the comments below or join the Strength and Conditioning Study Group on Facebook and ask them in that group as well. And we can have a discussion on energy systems. I love talking about this stuff. I hope you guys enjoyed the video. Make sure you like and subscribe to spread the knowledge and help others find the video. Thanks again for watching guys and I'll catch you in the next one.

We're not going to go over the details of any one energy system, but we're rather going to focus on how we actually use these energy systems during exercise. If we're doing weightlifting, interval training, endurance running, How are we actually shifting the utilization from one system to the other system and how are we actually getting training adaptations in these energy systems? Let's go ahead and dive into it. Alright, so we're going to start off by pulling this chart from page 54 of the Essentials of Strength Training and Conditioning book. And this chart is going to show us relatively which energy system is going to be providing the most energy during short bouts of high intensity effort versus during long bouts of low intensity efforts.

Alright, so importantly, this chart isn't showing us the number of ATP that are produced. Rather, this chart is showing us in column 1 the rate of ATP production from one system to the next. And basically...

which system is the fastest all the way down to which system is the slowest. And then exactly inverse to this, we're going to see the capacity for total ATP production in that second column. Again, this isn't the number of ATP produced, but rather this is the energy system that's going to be producing the most versus the least total amount of ATP. So let's just go one by one.

The ATP PC system here is going to produce ATP at the fastest rate. So this means that we're going to get ATP almost instantly. Within the first one, two seconds of exercise, we're going to be starting to produce ATP by splitting phosphocreatine molecules and basically giving that phosphate to an ADP to reform ATP. That happens right in the muscle very quickly and it can provide us with immediate energy.

But the downside of this system is that it depletes the fastest, meaning it runs out and we can't use this system for very long. I actually have a whole video on the ATP PC system, which I'll link down in the description below if you want more details about it. But just know that this is our fastest system, but it produces the least amount of ATP total.

All right, moving down to fast glycolysis, and you may have also heard of this as anaerobic glycolysis. This system is going to be the next in line. It's going to produce two net ATP per glucose molecule. And again, I have a full video that breaks this system down, but we're just going to focus on the big picture here. This system is going to produce two net ATP.

So it's going to give you a little bit more than the ATP PC system, which actually only produced one ATP, but it's going to take a little bit longer. That said, it is also going to give you a little bit more total. So it's going to be that next system down.

And the end product of fast glycolysis is going from glucose. So a glucose molecule being like a blood sugar molecule, breaking that down into pyruvate and then down into lactate. So that is the... the system of fast or anaerobic glycolysis and it's going to give us those two net ATP as well as produce some high energy substrates which can then be metabolized later. So some examples for these fast systems for the example of a shot put for example when we're putting a shot and it's just one quick effort that's primarily going to rely on the ATP PC system.

A secondary contributor is probably going to be fast glycolysis but that's pretty much what we're using from an energy system perspective for that exercise of shot put. And then here we'll start to reference this chart which will make it a little bit easier to understand the trade-offs or the mixed cases. So for the example of a 100 meter sprint if we're doing that in 11-12 seconds what you can see here is there's going to be a mixture of systems.

So the primary system this 11-12 second range is going to be anaerobic or fast glycolysis. But as you can see, there's some contribution from the ATP PC system that you see at the front of that chart, and there's some contribution from aerobic, but the primary system is that anaerobic glycolysis. So what this means, and this is oversimplified, but if it takes 100 ATP to run a 100 meter run, and again, that's very oversimplified, it takes thousands of ATP molecules, but let's just say it takes 100 ATP. This means that anaerobic glycolysis... might be giving you 50 or 60 of those ATP.

The ATP PC system might be contributing 30 of that 100, and then maybe we're getting a contribution of 10 or 20 from the aerobic system. So as you can see, the 50 or 60% of our energy that's coming from the anaerobic glycolysis or the fast glycolysis process makes it the primary energy system. Now, that doesn't mean that the... Other systems are turned off, but rather they're just secondary contributors to the energy production that you need for this duration of an event.

So any high intensity effort that's taking that 10 to 12 seconds, whether that be pole vaulting, whether that be a 100 meter run, a sprint or a breakaway in hockey, a run to first base in baseball, any of these types of plays that are taking about that 10, 15 seconds are going to primarily use that anaerobic glycolysis system. Alright, so getting back to the chart, we're going to talk about aerobic or slow glycolysis. And that's going to be kind of right in the middle. So for this energy system, we're getting a moderate amount of ATP and we have a moderate capacity for the system.

Meaning that it can produce a fair amount of ATP, but it also takes a fair amount of time. So just to be clear, slow glycolysis is referring to breaking down glucose into pyruvates and then sending it into the Krebs cycle and into oxidative phosphorylation to be fully oxidized. If that pyruvate was turned into lactate, that would be fast glycolysis or anaerobic glycolysis. And in this 30 to 90 second range, we're going to use a mixture of both.

If this video has been helpful for you so far, go ahead and smash that like button and subscribe so you don't miss any future videos. And also, make sure after you're done with this one, you check out all the videos in the description below if you want to learn more about one specific energy system. Alright, moving down the chart, we're going to talk about oxidation of carbohydrates. And this is a pretty broad term for saying...

Krebs cycle and oxidative phosphorylation. Those are really the processes that are occurring in the mitochondria where we're actually breaking down acetyl-CoA into CO2 and creating these high energy substrates which will then lead to the production of ATP. So the full oxidation of carbohydrate or the full oxidation of glucose involves going all the way from a glucose molecule to pyruvate.

through the Krebs cycle, through oxidative phosphorylation. And if we have the oxygen to go through all those steps and fully oxidize the glucose, we'll get to a total of 38 net ATP. So that's really what we're going to be talking about here in that fourth column, the full oxidation of carbohydrates.

And again, that's requiring oxygen, but it's referring to the breakdown of glucose. And in that case, it's going to be the fourth in terms of speed of energy production. We need to have oxygen.

We need to shuttle to the mitochondria. That takes time, but it's going to get a significant amount more ATP because again, breaking down one glucose molecule gets you all the way to 38 net ATP if you can oxidize the whole thing all the way through. Whereas if you're just doing glycolysis and you're ending at lactate, you're really only getting two net ATP.

So the amount is much greater than 38, but the rate is actually much less because it takes more time to fully oxidize than it does to just turn it right into lactate quick. This is going to be the primary energy system for most distance events anywhere from running 800 meters ish to uh multiple miles 10 20 miles. We're primarily going to be relying on this system.

As we get to really long events like a marathon we may get into the point where we're 50 50 between aerobic metabolism of carbohydrates and metabolism of fats and proteins primarily fats but it really takes long events to get to that point. For most endurance athletes we're going to be primarily using this carbohydrate metabolism and then that leads us into that final system oxidation of fats this is lipolysis and beta oxidation and i have a video that breaks this down as well but if we have a triglyceride which is a glycerol with three fatty acid chains we could first break the glycerol backbone off the fatty acids that's lipolysis and then we could chop up those fatty acids and that would be beta oxidation and those get chopped up into acetyl-coa which is then oxidized. So that whole process of breaking down triglycerides and breaking down fats all the way down to acetyl-CoA and then oxidation, it gets you a ton of ATP, 200 plus ATP actually, but it takes a lot of time to actually do that full process. A lot of oxygen is required.

So this is really just a secondary system at most distances. If you're running a 5k, a 10k. This may give you 30% of your energy, 35, 40% of your energy, again, depending on your training status.

But it really doesn't become a primary energy system until those really long duration events. If you guys still have any questions about energy systems, feel free to drop them in the comments below or join the Strength and Conditioning Study Group on Facebook and ask them in that group as well. And we can have a discussion on energy systems. I love talking about this stuff.

I hope you guys enjoyed the video. Make sure you like and subscribe to spread the knowledge and help others find the video. Thanks again for watching guys and I'll catch you in the next one.

Transcript for:Understanding Energy Systems in Exercise

Transcript for:
Understanding Energy Systems in Exercise