Lactic acid during anaerobic exercise

Muscle metabolizes glucose to lactic acid during exercise. Red blood cells depend upon anaerobic glycolysis for their energy source. 

Beyond this point, during more severe exercise associated with anaerobic metabolism, minute ventilation increases faster than the rate of oxygen consumption, but proportionally to the increase in carbon dioxide production. The mechanism of the ventilatory response to severe exercise involves metabolic acidosis caused by anaerobic metabolism. The lactic acid produced under these conditions liberates an H+ ion that effectively stimulates the peripheral chemoreceptors to increase ventilation. 

During strenous exercise there is little oxygen, 02, available for muscle cells. Under these conditions, the muscle cells derive most of their energy from the anaerobic conversion of pyruvic acid, C3H403, into lactic acid, C3H603. The buildup of lactic acid makes the muscles ache and fatigue quickly. Is the pyruvic acid oxidized or reduced as it transforms into lactic acid ... 

You can tiy working the other way, from the configurational label to the structure. Take lactic acid as an example. Lactic acid is produced by bacterial action on milk it s also produced in your muscles when they have to work with an insufficient supply of oxygen, such as during bursts of vigorous exercise. Lactic acid produced by fermentation is often racemic, though certain species of bacteria produce solely (R)-lactic acid. On the other hand, lactic acid produced by anaerobic respiration in muscles has the S configuration. 

The anaerobic threshold is the point during strenuous exercise at which anaerobic metabolism and lactic acid production begin." Carbon dioxide production (Vc02,max) increases with exercise at about the same rate as VO2, until the subject s anaerobic threshold is reached. From that point on, VCO2 increases faster than VO2, and this change can be used to estimate the anaerobic threshold. A breath-by-breath plot of the ventilatory equivalents for O2 and CO2 also can be used to determine the anaerobic threshold. Anaerobic threshold is a measure of fitness in normal subjects, and aerobic training can delay the anaerobic threshold. T ... 

Lactate, either as a salt or in its undissociated form (lactic acid), is present in minor quantities in our food. However, inside our body this monocarboxylic acid plays an important role in the exchange of substrates between organs. In this regard, lactate cannot be considered as a dead-end product of the anaerobic glycolytic pathway, but represents a substantial source of energy stored in carbohydrate during exercise and after a carbohydrate-rich meal (Brooks, 1991). 

Lactate production is a normal part of metabolism. In the absence of disease, elevated lactate levels in the blood are associated with anaerobic glycolysis during exercise. In lactic acidosis, lactic acid accumulates in blood to levels that significantly affect the pH (lactate levels greater than 5 mM and a decrease of blood pH below 7.2). 

During starvation, body fats replace dietary carbohydrates as a major source of energy. Metabolism of these fats yields organic acids such as acetoacetic acid. This causes a mild metabolic acidosis. In strenuous exercise, particularly in a trained athlete, fats are preferentially metabolized also, in exercise sufliciently strenuous to exceed the anaerobic threshold, lactic acid is released into the extracellular fluid in all subjects, both the trained athlete and the normal person. Fever and trauma such as extensive bums or major surgery result in tissue breakdown this catabolism results in the release of organic acids into the extracellular fluid. 

Several carboxylic acids are part of the metabolic processes within our cells. For example, during glycolysis, a molecule of glucose is broken down into two molecules of pyruvic acid, or actually, its carboxylate ion, pyruvate. During strenuous exercise when oxygen levels are low (anaerobic), pyruvic acid is reduced to give lactic acid or the lactate ion. 

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