Thread: Aerobic/Anaerobic Exercise

I've read that aerobic and anaerobic exercise are closely related, if not part of the very same process. Please explain...

in simple terms

aerobic processes use oxygen to turn biochemically stored energy into ATP which can then be used for running and jumping and all that jazz.

anaerobic processes also turn biochemical energy into ATP however they do this without the use of oxygen. It is less efficent than aerobic respiration and you get lactic acid build up. the lactic acid is what makes you unable to move the day after cross country =)

Originally Posted by gottspieler

I've read that aerobic and anaerobic exercise are closely related, if not part of the very same process. Please explain...

What sort of depth are you wanting? You want all the biochemistry behind it or did organic gods answer give you what you wanted? I wanted to revise all this soon so it would give me something to do (after the current essay I am doing is finished). you might have to wait a week though

Originally Posted by Molecular

Originally Posted by gottspieler

I've read that aerobic and anaerobic exercise are closely related, if not part of the very same process. Please explain...

What sort of depth are you wanting? You want all the biochemistry behind it or did organic gods answer give you what you wanted? I wanted to revise all this soon so it would give me something to do (after the current essay I am doing is finished). you might have to wait a week though

I want it all my friend.

although i hate to reference it wikipedia would probably be quite useful.

http://en.wikipedia.org/wiki/Aerobic_respiration

i just started a module in biochemistry, not a huge amount of depth to the lectures. but the background reading is fascinating

Nutrients commonly used by animal and plant cells in respiration include glucose, amino acids and fatty acids, and a common oxidizing agent (electron acceptor) is molecular oxygen (O2).

And what about the ingested molecules that aren't used in respiration? Iron, for example..or mercury...where are they primarily stored?

The energy released in respiration is used to synthesize ATP to store this energy. The energy stored in ATP can then be used to drive processes requiring energy, including biosynthesis, locomotion or transportation of molecules across cell membranes. Because of its ubiquity in nature, ATP is also known as the "universal energy currency".

Understood.

Aerobic respiration requires oxygen in order to generate energy (ATP). It is the preferred method of pyruvate breakdown from glycolysis and requires that pyruvate enter the mitochondrion in order to be fully oxidized by the Krebs cycle. The product of this process is energy in the form of ATP (Adenosine Triphosphate), by substrate-level phosphorylation, NADH and FADH2.

What is substrate-level phosphoration? (In a sentence or two, the Wiki article is too complicated for me at this point.)

Molecular, plz critique...from Body by Science by Dr. Doug McGuff:

Energy 1st enters the cell in form of glucose, a sugar derived from food breakdown. Once in the cell, glucose is metabolized in the cytosol portion of a cell anaerobically through 20 some chemical reactions until it becomes pyruvate. This is known as anaerobic metabolism. Pyruvate then is moved inside mitochondria where it is metabolized through a complex process, making use of the Krebs Cycle and respiratory chain. This process converts pyruvate to a total of 36 molecules of ATP. This is known as aerobic metabolism.

The Krebs Cycle and respiratory chain can produce a lot of energy in the form of ATP yet they are slow. By comparison, glycolosis (the process by which glucose is metabolized in cytosol to form pyruvate) produces only 2 molecules of ATP during life-or-death circumstances or exertion. If well-conditioned, however, one can alter the glycolytic cycle into an accelerated state and supply a lot of energy to working muscles for a long period of time.

If our muscles require energy during high-intensity exercise or in an emergency, most ATP used will be derived from rapid-cycling of the glycolytic cycle. As this occurs, lactate can quickly accumulate, but this is not necessarily the end of the road. Lactate formed from this process quickly diffuses from muscles into bloodstream and then to the liver. In the liver, lactate is converted back into pyruvate, which is then converted to glucose by gluconeogenesis. Glucose thus formed is transported out of the central vein of the liver and made available again for use by working muscles, or, if exertion ends, glucose can be stored as glycogen, which is simply a polymer, or chain, of glucose molecules. This process is known as the Cori Cycle.

When you exersize intensely enough, lactic acid builds and the resulting hydrogen ions are released into the blood and act on haemoglobin molecules to changetheir shape so that they have less of an affinity for oxygen. This results in better oxygen delivery to tissues. With extremely good conditioning, you will begin to synthesize 2,3 diphosphoglycerate (2,3 DPG) and it works like the Bohr Effect (where oxygen uptake is sacrificed in lungs for better tissue delivery), but long term.

Excess energy forms adipocytes (fat cells) in the form of triacylglycerol. During severe muscular exertion, adrenaline and glucagon stimulate triacylglycerol mobilization by activating hormone-sensitive lipase enzyme. This enzyme binds to albumin, a protein that transports these fatty acids to muscles for beta-oxidation to form 35 molecules of ATP. Moreover, glycerol, an intermediate step in the process, can travel to the liver and convert to glucose which can undergo further oxidation that can produce 96 ATP molecules. Thus high-intensity training does burn fat.

At the point where your glycogen stores become completely full, glucose can;t be rammed down the path of glycogen synthesis and is destined tobecome fat. When glucose levels are high and glycogen stores are full, phosphofructokinase enzyme (involved in glucose metabolism) is inhibited. Glucose can only go to the level of fructose-6-phosphate on the glycolysis cycle and then gets shunted to pentose phosphate path, which will convert glucose eventually to glyceraldehyde 3 phosphate (G3P), a fat precursor. There are several more steps, then NADH is formed, which fuels fatty acid synthesis. Full glycogen stores along with high carbohydrates stimulates fatty acids, especially in the liver and drives up LDL cholesterol.

Originally Posted by gottspieler

Molecular, plz critique...from Body by Science by Dr. Doug McGuff:

Energy 1st enters the cell in form of glucose, a sugar derived from food breakdown. Once in the cell, glucose is metabolized in the cytosol portion of a cell anaerobically through 20 some chemical reactions until it becomes pyruvate. This is known as anaerobic metabolism. Pyruvate then is moved inside mitochondria where it is metabolized through a complex process, making use of the Krebs Cycle and respiratory chain. This process converts pyruvate to a total of 36 molecules of ATP. This is known as aerobic metabolism.

The Krebs Cycle and respiratory chain can produce a lot of energy in the form of ATP yet they are slow. By comparison, glycolosis (the process by which glucose is metabolized in cytosol to form pyruvate) produces only 2 molecules of ATP during life-or-death circumstances or exertion. If well-conditioned, however, one can alter the glycolytic cycle into an accelerated state and supply a lot of energy to working muscles for a long period of time.

If our muscles require energy during high-intensity exercise or in an emergency, most ATP used will be derived from rapid-cycling of the glycolytic cycle. As this occurs, lactate can quickly accumulate, but this is not necessarily the end of the road. Lactate formed from this process quickly diffuses from muscles into bloodstream and then to the liver. In the liver, lactate is converted back into pyruvate, which is then converted to glucose by gluconeogenesis. Glucose thus formed is transported out of the central vein of the liver and made available again for use by working muscles, or, if exertion ends, glucose can be stored as glycogen, which is simply a polymer, or chain, of glucose molecules. This process is known as the Cori Cycle.

When you exersize intensely enough, lactic acid builds and the resulting hydrogen ions are released into the blood and act on haemoglobin molecules to changetheir shape so that they have less of an affinity for oxygen. This results in better oxygen delivery to tissues. With extremely good conditioning, you will begin to synthesize 2,3 diphosphoglycerate (2,3 DPG) and it works like the Bohr Effect (where oxygen uptake is sacrificed in lungs for better tissue delivery), but long term.

Excess energy forms adipocytes (fat cells) in the form of triacylglycerol. During severe muscular exertion, adrenaline and glucagon stimulate triacylglycerol mobilization by activating hormone-sensitive lipase enzyme. This enzyme binds to albumin, a protein that transports these fatty acids to muscles for beta-oxidation to form 35 molecules of ATP. Moreover, glycerol, an intermediate step in the process, can travel to the liver and convert to glucose which can undergo further oxidation that can produce 96 ATP molecules. Thus high-intensity training does burn fat.

At the point where your glycogen stores become completely full, glucose can;t be rammed down the path of glycogen synthesis and is destined tobecome fat. When glucose levels are high and glycogen stores are full, phosphofructokinase enzyme (involved in glucose metabolism) is inhibited. Glucose can only go to the level of fructose-6-phosphate on the glycolysis cycle and then gets shunted to pentose phosphate path, which will convert glucose eventually to glyceraldehyde 3 phosphate (G3P), a fat precursor. There are several more steps, then NADH is formed, which fuels fatty acid synthesis. Full glycogen stores along with high carbohydrates stimulates fatty acids, especially in the liver and drives up LDL cholesterol.

All this stuff is well researched and if it is from that book it is probably all right. As far as I am aware there is no controversy regarding aerobic and anaerobic metabolism. Since Peter Mitchell proposed the chemiosmotic hypothesis it was all figured out. Most 'normal' textbooks on this area are probably adequate for learning all this. If you have any specific questions then feel free to ask though.

All this stuff is well researched and if it is from that book it is probably all right. As far as I am aware there is no controversy regarding aerobic and anaerobic metabolism. Since Peter Mitchell proposed the chemiosmotic hypothesis it was all figured out. Most 'normal' textbooks on this area are probably adequate for learning all this. If you have any specific questions then feel free to ask though

For now, only one question:

What about the ingested molecules that aren't used in respiration? Iron, for example..or mercury...where are they primarily stored?

Originally Posted by gottspieler

What is substrate-level phosphoration? (In a sentence or two, the Wiki article is too complicated for me at this point.)

Its the transfer of a phosphate group from a high energy intermediate [En] in a metabolic process to adenosine diphosphate [ADP] to form adenosine triphosphate [ATP]

En~P + ADP = ATP + En

Here is a simple animation that explains the process.

http://student.ccbcmd.edu/biotutoria...y/subphos.html

Both in similar in that they must make ATP to power the muscles. They are different in their mechanism.

In aerobic, ATP is gained through aerobic glycolysis and the citric acid cycle.

In anaerobic, ATP is gained trhough anaerobic glycolysis (with a byproduct of lactic acid) and also through the creatine phosphate system.

Aerobic is generally an endurance activity, like jogging, walking, or pretty much anything you're doing throughout your day.

Anaerobic is things like weightlifting and sprinting. Things that you can't sustain for very long.

The anaerobic process is less about producing ATP, but more about regenerating NAD+ to keep glycolysis going.

I also wouldn't classify the creatine phosphate system as anaerobic respiration either.

Frankly it is best for the beginner to ignore amino acid and fatty acid metabolism. It involves a whole slew of different enzymes and basically what it boils down to is that they are all turned into intermediates of glycolysis anyway.

As for mineral absorption it depends on the mineral. They aren't used for energy though. Mostly they float around in the blood on carrier proteins until a cell that needs them picks them up.

Knowing a bit about aerobic vs anaerobic excercise can improve your training regimen. Say you're running uphill. Taking shorter steps can make you work below your metabolic threshold. It will tax you aerobicly which means you'll breathe harder, but recover quicker.

Although potentially detrimental to knees if practiced improperly, taking longer steps may be preferable for some types of training where anaerobic exercise, similar to weight lifting is the goal. This type of hill work is benificial once a week, maybe before a rest day.

Originally Posted by i_feel_tiredsleepy

The anaerobic process is less about producing ATP, but more about regenerating NAD+ to keep glycolysis going.

I also wouldn't classify the creatine phosphate system as anaerobic respiration either.

Frankly it is best for the beginner to ignore amino acid and fatty acid metabolism. It involves a whole slew of different enzymes and basically what it boils down to is that they are all turned into intermediates of glycolysis anyway.

As for mineral absorption it depends on the mineral. They aren't used for energy though. Mostly they float around in the blood on carrier proteins until a cell that needs them picks them up.

Huh? The anaerobic process is ALL about producing ATP. When you sprint for the bus, rather than casually stroll and miss it, your primary requirement is the necessity for quick high burst energy, even if you sacrifice endurance by needing to stop and pant once you get in.

And no, you cannot ignore amino acid and fatty acid metabolism. The fact that they require oxygen for ATP production is a limiting factor in their use as fuel for anaerobic energy production.

Originally Posted by samcdkey

Huh? The anaerobic process is ALL about producing ATP. When you sprint for the bus, rather than casually stroll and miss it, your primary requirement is the necessity for quick high burst energy, even if you sacrifice endurance by needing to stop and pant once you get in.

And no, you cannot ignore amino acid and fatty acid metabolism. The fact that they require oxygen for ATP production is a limiting factor in their use as fuel for anaerobic energy production.

You miss the point, the reason we need the anaerobic process is to cycle NAD the limiting factor that prevents us from just pumping pyruvate through the Krebbs cycle.

And yes a beginner with no prior knowledge of biochemistry should ignore amino acid and fatty acid metabolism. They exist, but the specific processes aren't necessary for him to understand. You can just keep going on and on, should we discuss the oxidation of brown fats for the generation of heat, since it's an anaerobic process. I think it's sufficient to speak about glycolysis and the metabolism of glucose for him to reach a general understanding of how anaerobic and aerobic respiration differ.

Originally Posted by i_feel_tiredsleepy

You miss the point, the reason we need the anaerobic process is to cycle NAD the limiting factor that prevents us from just pumping pyruvate through the Krebbs cycle.

This is backwards logic for me. IMO, the aim of glycolysis or Krebs is to produce ATP, the difference is speed of ATP generation and clearance of lactate, both of which are limiting factors for fatigue and recovery. NAD, FAD etc are just electron carriers. Consider, for example, fermentation.

Yes but what is limiting the availability of ATP is the availability of NAD.

Really the reason fermentation is necessary in the absence of oxygen is that NADH produced in glycolysis needs to be oxidized to keep glycolysis going. The ATP produced by fermentation is relatively minute. Without available NAD, glycolysis comes to a complete stop.