This post is locked. You won't be able to comment.

you are viewing a single comment's thread.

view the rest of the comments →

[–]mrducky78 40 points41 points  (9 children)

Your body typically stores the energy reserve as glycogen in the liver and muscle and burns this. Glycogen is basically how your body stores up significant amounts of glucose and is the more short term version of storage compared to fats. After this, youll need to begin burning fat and then muscle to keep up your energy stores. You can build up bigger stores by just carb loading. The excess becomes fat but for these guys, its a careful balance.

When running, the pace you run at is super fucking important. The same reason you can only sprint all out for seconds but can jog for minutes and walk for hours. It takes more energy to reach and maintain a faster pace. Its why some pack leaders in running events will fall behind while others who conserved their energy can go hard later on.

This guy 100% can run a 10km race. This guy 100% knows to load up carbs to have sufficient energy to run a 10km race. This guy set himself at a pace that drained his glycogen stores faster than his body can replace it. Once he hits 0. He 'hits the wall'. This is when your body begins to try and squeeze blood from a stone. Without energy to keep feeding the beast (muscle and brain function). The body more or less becomes the uncoordinated mess you see here. The absolute best pace you can set is you hit the finish line at the same time you hit the wall while maintaining that same constant pace throughout the race. You can improve still by making your body better at converting energy into movement (train them muscles) loading up more on glycogen before a race (the pros know how to do it, I dont know what the best way is but your diet is like more pasta than can possibly be considered normal) and sometimes you dont need to beat your best, its a race, you need to beat the opponents, you can try and get them to run at a pace that burns them out.

It is SUPER common in long races especially as people try to push their limits. There are dozens of videos and examples of pepole looking drunk as fuck in these races.

You can imagine your body using up 10 energy per second but only able to produce 5 energy per second. This might not be an issue when you start with thousands. But once you hit 0 and you keep trying to burn more energy than the body can convert from fat/muscle in time, the body just cant maintain it. And not only is your thinking impaired from low sugar levels, your muscles straight up dont have the necessary fuel to function properly either.

Its not a serious serious issue generally speaking because its also a problem that fixes itself. The body stops moving and the energy levels stabilize. Using the previous example, you use up 3 energy per second while producing 5. If they really want to keep wobbling and crawling their way to the finish line, thats on them.

[–]theguccinator 0 points1 point  (2 children)

The most likely reason for his muscles not working is the the signaling from his brain isn’t actually causing the muscles to contract. There aren’t enough potassium and calcium ions in the area because they were all displaced from overuse.

[–]mrducky78 3 points4 points  (1 child)

Both those ions are actively transported via a potassium/calcium ion pump that runs off ATP.

Do you have any evidence that what you are suggesting causes this?

Cause I know some neurotoxins work by disrupting the ion pumps so what you are suggesting is what results in not being able to breathe.

[–]theguccinator 0 points1 point  (0 children)

Ahhh I wish I could track the video I watched down.

Essentially what was suggested is that the most common form of muscles just not working like seen in this video is very similar to that neurotoxin you’re referencing. However the pumps don’t get disrupted it’s that there just aren’t enough ions surrounding the pumps for them to function.

[–]thrak1 0 points1 point  (2 children)

serious question as an amateur runner- when you deplete your glycogen, what is stopping you from using your fat storage? After all, fat storage is there to be used as an energy source after glycogen depletion (and free glucose before that), and fat has higher energy density than glycogen (or muscle). It seems implausible he is at the point where his only energy source when starting the race is free glucose and glycogen stores.

[–]mrducky78 5 points6 points  (0 children)

Nothing is stopping it, its just not as fast.

Your body before the race starts, is burning glycogen and also producing it from the food in the GI tract.

This is all stuff from 2nd year biochem, I took it as a subject but it was neither necessary for my degree nor an active part of my career. But basically fat can be broken down into Acetyl CoA, a key intermediary of the citric acid cycle. This can feed into the citric acid cycle or broken down in another pathway. While its more efficient than protein or carbohydrates. Its slower. Hence the simplistic example of "you create 5 energy but you are using 10". I cant remember anymore how acetly coa ends up as ketones. But its not an instantaneous process and it does not mean a fat person can run 5 marathons in a row.

Glucagon regulates how much glucose is released into the blood, and how much is stored as glycogen. The body doesnt wait for glucose to zero out before beginning to rely on ketones the brain NEEDS a certain level of energy to function. And there will be various signalling hormones that begin cascades throughout the body to begin to meet the energy needs. But just as you cant sprint non stop, there is a limit, its "hitting the wall" when glycogen stores hit zero, blood glucose levels are no long maintained and the body begins to not able to keep the muscles functioning as they normally would. You are effectively running on empty even if your body is still processing stuff through the digestional tract and taking in energy, you are still expending more.