I took a physiology course so you don’t have to! I’ve combined some surprising basics with key terms and research on myalgic encephalomyelitis (aka chronic fatigue syndrome) into less than six minutes. And I’ve tried to keep it fairly simple.
Here’s the script:
In a previous video, I described how ME/CFS limits our energy even on good days. In this one, I describe, in simplified terms, how human cells produce energy more generally. And I show how some of the research on ME/CFS fits in. The details might hold some surprises; they did for me.
Until recently, I didn’t think much about how my body produced energy. I guess I assumed that there was just one way that it happened.
Not true! To better understand ME/CFS, I’ve studied a bit of physiology, and I’ve learned a few basic things. Generally:
- Energy is produced in the same cell that uses it.
- The main fuel that our cells produce and consume is ATP, which is just a molecule.
- Cells have three main ways to produce ATP.
- This is my focus in this video.
Healthy cells have three main ways of producing fuel, or ATP. To make them easier to remember, I’ll call them: the flamethrower, kindling, and firelogs. I’ve shown their scientific names, too. Note that the first two are “anaerobic,” which means that they don’t require oxygen. Note also that, optimally, the second process, glycolysis or kindling, should feed into the third process.
Let’s recall that our bodies are made up of tiny cells that aren’t much bigger than germs. And almost all of our bodies’ business either takes place in cells or consists of transportation and communication between cells. In fact, our fuel is produced inside the same cells that use its energy, but the raw materials for this fuel, such as sugar or fat, are transported in the blood from other parts of the body to cells that need it.
Okay, back to the three main ways to produce fuel in cells. Let’s start with the flamethrower (or ATP-PCr System). I call it a flamethrower because it’s ready in an instant and it gives a cell (for example in a muscle) a short burst of explosive power. A cell will store a batch of PCr (or phosphocreatine) for a short burst. After 10-15 seconds of all-out exercise, though, it’s gone.
As far as I have read, researchers haven’t consistently found problems with the flamethrower in ME/CFS. So maybe most people with this disease have at least a few seconds of burst in them. On the other hand, I’ve been through tough times when it was even harder to start moving than it was to continue. When a person starts to move, cells use a small, built-up store of ATP while triggering the flamethrower and ramping up the other two systems. So I wonder whether the flamethrower worked but the baseline level of ATP was deficient.
Here I should note that all three types of fuel-production take place at the same time. One just predominates at any particular moment.
On we go to kindling (or glycolysis), which converts the sugar glucose into energy. Glycolysis is like kindling for two reasons:
- It doesn’t produce much energy
- During all-out exercise, it lasts for about a minute.
- And it should feed pyruvate into the stronger and long-lasting energy-production of the third type (“firelogs”). In ME/CFS it doesn’t, which is the subject of my first video.
Once again, there might not be a problem with glycolysis among people with ME/CFS. Or maybe the problem is that there is no problem, leading to lactate build-up.
The third and most powerful form of fuel production is the firelog (or oxidation). This is also called aerobic energy. Firelogs provide a lot of energy for a long time, and this third method has the same advantages in producing ATP. Oxidation takes a little longer to get started than the other two. It occurs in the mitochondria and is quite complex. For example, it includes a chain of processes called the Krebs Cycle or Citric Acid Cycle and another called the Electron Transport Chain.
Just as firelogs can come from different types of trees or recipes, our cells can use different raw materials for oxidation. The most efficient one, pyruvate, comes from glucose via the kindling process. In a healthy person, the fuel produced from glucose can last for about 90 minutes of exercise.
Then the body will switch its emphasis to converting fat to energy. Even a skinny person has days of fat stored here and there. But people can’t produce ATP from fat as quickly as from sugar. And it takes more oxygen. So, all in all, it’s an inferior method.
In a pinch, our cells can also use the building blocks of proteins — amino acids — as firelogs too.
Unfortunately, a lot of research indicates that the preferred firelog, from glucose, doesn’t get used in the cells of people with ME/CFS. Instead, it piles up in the form of lactate, which causes various problems, such as pain and weakness. That is, there’s a problem in the transition from kindling to firelog – as described in my other video. So, after our free 15 seconds, we end up depending on kindling and then on inefficiently burning fat and amino acids.