Energy system question

An athlete has been running marathons for the past 10 years. His best marathon time is 2 hours and 10 minutes.

How is the ATP resynthesised in the predominant energy system used in a marathon event. The predominant energy system is the Aerobic system

I know that the ATP/CP system is used for short bursts of energy such as sprints or powerful movements like high jump but how does it relate back to the completely different energy system of the Aerobic system?
 
Mitochondria.
 
i made my own answer but feel free to comment on anything that is wrong.

The predominant energy system used in a marathon is the aerobic system. ATP production is slowly increased in the aerobic system as the oxygenated blood starts to flow throughout the muscle cells. The Aerobic system is now the main supplier of ATP and this process is sometimes called aerobic metabolism. Fat, glucose and sometimes protein depending on the intensity of the activity are broken down with the presence of oxygen to produce the ATP.
 
The ATP/CP system (andonsin triphosphate/creatine phosphate) is the energy system used for explosive movements but is exhausted within 10-12 seconds. The human body has 60 grams of it stored throughout muscle cells. When CP supplies are gone the muscles can no longer sustain maximum power output and must slow down as a result. CP is refueled within 2 to 2 and a half minutes while resting.
 
yeah, something like that. I dunno exactly how much ATP and PC the body has stored though, I think I've heard more than 60g, but you probably get different numbers depending on your source. If you want to know more about this sort of thing you should pick up an exercise physiology text book. Or if you know chemistry, a biochemistry textbook, which will usually cover it in much more detail with more attention payed to the chemical formulas and other details.
 
It's a totally different system and would be minimal in any marathon.

"ATP production is slowly increased in the aerobic system as the oxygenated blood starts to flow throughout the muscle cells."

I wouldn't write this because oxygenated blood always flows through muscle.

"The ATP/CP system (andonsin triphosphate/creatine phosphate) is the energy system used for explosive movements"

I'm sure your teacher would say a big no no to that to ;) This statement implies the ATP-PC system is the only system working during explosive movement, which is incorrect. Chuck in the word predominant.
 
It's a totally different system and would be minimal in any marathon.

"ATP production is slowly increased in the aerobic system as the oxygenated blood starts to flow throughout the muscle cells."

I wouldn't write this because oxygenated blood always flows through muscle.

"The ATP/CP system (andonsin triphosphate/creatine phosphate) is the energy system used for explosive movements"

I'm sure your teacher would say a big no no to that to ;) This statement implies the ATP-PC system is the only system working during explosive movement, which is incorrect. Chuck in the word predominant.

Those are some very good points.

I know that something a lot of people didn't quite understand last year in my work physiology class is that all the energy systems really work at the same time, it's just a matter of which one works the most. It takes a while for the aerobic energy system to get going properly, so even when you're running at low intensities, the start of the run will rely heavily on the ATP/PCr and anaerobic glycolysis, then as the aerobic system catches up you don't have to be that anaerobic anymore because the mitochondria has it's capacity up and can deal with all the NADH from glycolysis (which would otherwise go like this NADH + pyruvate would become: NAD + lactate- + H+, in order to "recycle" the NAD because it's key in the glycolysis. I don't know if that's too detailed for you RWS).
If you then start running faster, the body will need ATP so quickly that the mitochondria can't keep up with it. Glycolysis can go a lot faster, so glycolysis speeds up and again like in the begining, the mitochondria can't handle all of the NADH that is created in the glycolysis. Now keep in mind, that doesn't mean the mitochondria isn't working, it's taking all the NADH it can, it's just not enough so some is left to accumilate, and that will be taken care of by the pyruvate - lactate reaction which takes up the H+ from the NADH and one H+ from the solution. This is necessary to free up NAD+

And yeah, when you do explosive stuff you need energy so fast that ATP/PCr will be the main source, since it's the fastest reaction.

I think to really understand this you need some knowledge about how it works.

I hope I didn't make any stupid mistakes in this post BTW, though there is a big possibility I screwed something up.
 
Thanks Karks. Yeah that sounds right.

I also noticed this "How is ATP resynthesised in the aerobic energy system"

I might be a little rusty myself, but i'm pretty sure the ATP from the aerobic system is used to do work and isn't resynthesised per se. That's why it needs a continuous source of energy i.e glucose.
 
The predominant energy system used in a marathon is the aerobic system. ATP production is slowly increased in the aerobic system as more and more oxygenated blood starts to flow throughout the muscle cells. The Aerobic system is now the main supplier of ATP while the aerobic system is working and this process is sometimes called aerobic metabolism. Fat, glucose and sometimes protein depending on the intensity of the activity are broken down with the presence of oxygen rich blood to produce the ATP. ATP is not the main source of energy in a marathon event but this is how the aerobic energy system resynthesizes ATP as it is required for the aerobic system to work. The 3 energy systems Alactacid, Lactic acid and Aerobic system all work together at the same time but depending on the type of exercise one will be the main provider of energy. The 3 systems work to create new energy for the body until the body reaches maximum energy output and glucose is exhausted. At this point the aerobic system starts to tap into the fat stores and later the protein stores.

better?

If any one would like to word it better for me please do because i am terrible at writing :)
 
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An athlete has been running marathons for the past 10 years. His best marathon time is 2 hours and 10 minutes

Question

Explain the type of training this athlete would undertake and use your knowledge of energy systems to justify your answer
 
ATP is not the main source of energy in a marathon event but this is how the aerobic energy system resynthesizes ATP as it is required for the aerobic system to work.

All the systems utlise ATP for energy. The difference is where and how it gets it. The aerobic system gets it from stored potential energy (glucoce, fat) which undergoes the Krebs cycle. Anaerobic makes ATP from glucose and does not use the Krebs cycle.

The 3 systems work to create new energy for the body until the body reaches maximum energy output and glucose is exhausted. At this point the aerobic system starts to tap into the fat stores and later the protein stores.

Just like all the systems working together, glycogen and fat work together to provide energy. Fat is being used during marathon running, not merely when the athelete has exhausted glucose supplies. In fact, well trained athelets get most of their ATP from fat as it prolongs the feeling of fatigue as glucose levels are preserved for longer.
 
Thanks Karks. Yeah that sounds right.

I also noticed this "How is ATP resynthesised in the aerobic energy system"

I might be a little rusty myself, but i'm pretty sure the ATP from the aerobic system is used to do work and isn't resynthesised per se. That's why it needs a continuous source of energy i.e glucose.

I'm guessing by resynthesised he means how ATP is split into ADP and Pi, then ADP and Pi is "fused" together again into ATP in these different energy systems. so in a way you resynthesise it. and the energy needed for the resynthesisification (yes, I just made a new word) is taken from the reactions in the different energy systems.

And smith, this is sounding more and more like homework :p what kind of studies do you do?
 
this should help
 
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