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Old 09-18-2013
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Biochemistry Lactate in Energy and Exercise!

During exercise body needs more energy which is only possible if citric cycle and oxidative phosphorylation increases BUT they actually inhibited due to increase NADH..and pyruvate converted to lactate ..WHY????

does lactate produce more energy ??if yes how?
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Old 09-19-2013
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This depends on the number of mitochondria in the tissues , in athletes they have much mitochondria than normal individuals so they have more time before shift to anaerobic glycolysis..

Shifting to anaerobic pathway produces pain which is warning sign to terminate the exercise soon due to reaching maximum activity of aerobic pathway

Hope you finds this useful
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Old 09-19-2013
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It means lactate has nothing to do with energy?
It is only a warning sign to reduce activity?
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Old 09-20-2013
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I thought it was the lack of oxygen?
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Old 09-20-2013
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Not exactly

Look , when you use the aerobic pathway to produce ATP , there are two events would stop the aerobic respiration

1- you produced lots of ATP so it will inhibit the glyclosys pathwat and also no NADH will be oxidized anymore so NADH will inhibit the pathway because you dont need ATP anymore

2- the mitochondria are working and producing ATP in a rate less than what your body actually needs , either due to low number as in sedentary life or due to insufficient oxygen

This time the body is forced to go through the anaerobic pathway , it will profuce ATP but very low so the lactate pathway beside supplying body with some energy will warn the body by pain that he cant exercise more , if you dont have such threshold you may progress to clonus as the process of relaxation of muscles needs energy , this is why when you have vigorous exercise you experience pain so you stop when you cant bear it , after that twitches in muscles are felt due to partial clonus ...if no pain you would have proceeded more in exercise till complete clonus appears ..other example is silent MI in diabetics , only pain gives a hint that there is a problem and in diabetes there is no pain and patients pass away

Wish you got it
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Old 09-20-2013
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Quote:
Originally Posted by Seeking260 View Post
Not exactly

Look , when you use the aerobic pathway to produce ATP , there are two events would stop the aerobic respiration

1- you produced lots of ATP so it will inhibit the glyclosys pathwat and also no NADH will be oxidized anymore so NADH will inhibit the pathway because you dont need ATP anymore

2- the mitochondria are working and producing ATP in a rate less than what your body actually needs , either due to low number as in sedentary life or due to insufficient oxygen

This time the body is forced to go through the anaerobic pathway , it will profuce ATP but very low so the lactate pathway beside supplying body with some energy will warn the body by pain that he cant exercise more , if you dont have such threshold you may progress to clonus as the process of relaxation of muscles needs energy , this is why when you have vigorous exercise you experience pain so you stop when you cant bear it , after that twitches in muscles are felt due to partial clonus ...if no pain you would have proceeded more in exercise till complete clonus appears ..other example is silent MI in diabetics , only pain gives a hint that there is a problem and in diabetes there is no pain and patients pass away

Wish you got it
Yeah I got it and I understand. But I just remembering that Dr. Turco mentioning that the main reason for it not to go into the mito was the lack of oxygen because no matter how trained you are there's just not enough oxygen to be delivered!

Let's seek that 260 together haha
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Old 09-20-2013
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Thanks BUT whatz the advantage of recycling NADH cuz glycolisis is inhibited and no more pyruvate to produce ATP.
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Old 09-20-2013
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You still produce ATP and the Lactate will enter Cori's cycle to be back in Pyruvate.
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