When is lactic acid made

The liver converts it back into sugar; the heart converts it into pyruvate. During exercise, concentrations of lactic acid in the body do spike because the heart and liver can't deal with the waste product as quickly as it's produced. But as soon as we're done exercising, lactic acid concentrations go back to normal, Gleeson said. Related: Feel the pain? Don't blame lactic acid. Muscle soreness after exercise most likely has more to do with tissue damage and inflammation , Gleeson said.

Hard exercise physically breaks down your muscles, and it can take days for them to recover. Lactic acid can build up to life-threatening levels in the body, according to a review published in the Mayo Clinic Proceedings.

But this condition, called acute lactic acidosis, happens because of acute illness or injury, not exercise. When tissues are deprived of blood due to a heart attack or sepsis , for example, they tend to go into anaerobic respiration, producing lactic acid.

But Gleeson said he's never heard of a case of life-threatening lactic acidosis because of exercise. Isobel Whitcomb, a contributing writer for Live Science, covers the environment, animals and health.

Isobel's roots are in science. Lactate Threshold. Lactate is actually a product of cellular metabolism and is produced in various cells throughout the body including muscles, brain cells and red blood cells. Lactate and lactic acid are actually used as a fuel by some tissues in the body including neurons and cardiac heart muscle. Skeletal muscle cells that produce lactic acid Credits Lactic Acid. The fact is there is so much more to lactate than its supposed role in acidifying the cellular contents of muscle a myth that can easily be deconstructed and it is integral to our existence.

What Is Lactic Acid? Why Is Lactic Acid Produced? Where is Lactic Acid Produced? How is Lactic Acid Produced? What Happens to Lactic Acid? Measuring Lactic Acid Levels. Lactic Acid — The Truth. This energy comes from glucose through a process called glycolysis, in which glucose is broken down or metabolized into a substance called pyruvate through a series of steps. When the body has plenty of oxygen, pyruvate is shuttled to an aerobic pathway to be further broken down for more energy.

But when oxygen is limited, the body temporarily converts pyruvate into a substance called lactate, which allows glucose breakdown—and thus energy production—to continue. The working muscle cells can continue this type of anaerobic energy production at high rates for one to three minutes, during which time lactate can accumulate to high levels.

A side effect of high lactate levels is an increase in the acidity of the muscle cells, along with disruptions of other metabolites. The same metabolic pathways that permit the breakdown of glucose to energy perform poorly in this acidic environment. On the surface, it seems counterproductive that a working muscle would produce something that would slow its capacity for more work. In reality, this is a natural defense mechanism for the body; it prevents permanent damage during extreme exertion by slowing the key systems needed to maintain muscle contraction.

Contrary to popular opinion, lactate or, as it is often called, lactic acid buildup is not responsible for the muscle soreness felt in the days following strenuous exercise. Rather, the production of lactate and other metabolites during extreme exertion results in the burning sensation often felt in active muscles, though which exact metabolites are involved remains unclear.