Table of ContentsView AllTable of ContentsWhat Is the Cori Cycle?Why Is It Important?Where Does It Occur?Steps of the Cori CycleLimitationsCori DiseaseFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
What Is the Cori Cycle?
Why Is It Important?
Where Does It Occur?
Steps of the Cori Cycle
Limitations
Cori Disease
Frequently Asked Questions
The Cori cycle is a natural, metabolic pathway that was named after its discoverers, Carl Ferdinand Cori and Gerty Cori in 1929.It is sometimes referred to as the lactic acid cycle because it involves the production of lactate. The Cori cycle occurs when the muscles need energy.
This article discusses how the Cori cycle works, why it’s important, where it occurs, its steps, limitations, and more.
Lactic Acid for Skin to Smooth Lines and Even Complexion
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Our muscles require glucose (sugar) for energy during exercise. However, when a person is exercising strenuously, oxygen may not reach the muscles fast enough to keep up with the workout. This is known as anaerobic exercise, any exercise that occurs in the absence of oxygen. This need for quick energy triggers the Cori cycle.
The Cori cycle involves an exchange between the muscles and the liver to allow the body to use carbohydrates for energy. This is because our cells cannot use lactate for energy.
To sustain energy while exercising, lactate must leave the muscle cells and be transported through the circulation to the liver, where it is converted back to glucose so the muscle cells can use it. Once glucose is returned to the muscles, the cells can use it for energy, and glucose is either turned back to lactate or stored.
Understanding Anaerobic Exercise
Why Is the Cori Cycle Important?
Once this process takes place, the muscles can then use glucose for energy. Gluconeogenesis is the pathway in which glucose is produced in the body.
When lactate builds up in the muscles, it can decrease exercise performance. When it is not removed, it can cause the muscles to become acidotic. The Cori cycle is the body’s natural mechanism for removing lactate and prevents lactate from building up in the muscles.
What Is Blood Sugar?
Where Does the Cori Cycle Occur?
The Cori cycle occurs between the muscles and the liver in the cytoplasm of the cells.It also occurs in red blood cells, in immune cells in the lymph, in cells in the bone marrow, and in cells in the skin.The renal (kidney) tubules are also involved in the process.
These are the steps of the Cori cycle during exercise, prolonged fasting, and injury:
Limitations of the Cori Cycle
The Cori cycle is not meant to be used long-term and is not as efficient as the body’s usual energy process called the Krebs cycle. When the muscles do not have enough oxygen to sustain activity, lactate can build up.
The problem is that after prolonged periods of time, lactate accumulation occurs and muscles may begin to fatigue. In addition, the Cori cycle’s recycling of glucose cannot be sustained indefinitely because it costs more energy than it creates.
Glycogen Storage Disease Type III (Cori Disease)
GSD-III is inherited as an autosomal recessive trait and has an incidence of about 1 in 100,000 in the United States. The inability to produce or break down glycogen can cause low blood sugar (hypoglycemia), enlarged liver (hepatomegaly), failure to thrive, and recurrent illness or infections. Treatment includes dietary changes that focus on protein-rich foods and monitoring blood sugar and ketones.
Summary
A Word From Verywell
The Cori cycle is an important way for your body to utilize energy while exercising. If you have ever experienced muscle fatigue or soreness during an intense workout, you have likely felt the effects of lactic acid. Work with your healthcare provider to develop the right physical activity plan for you.
Frequently Asked QuestionsThe purpose of the Cori cycle is to provide energy to the muscles during exercise while removing lactate and preventing lactic acidosis.The Cori cycle is not sustainable because it costs more energy than it creates, and glycogen stores in muscles are limited.The Cori cycle causes the recirculation of glucose back to muscle tissue for the use of energy during exercise.Gluconeogenesis is important in the Cori cycle because lactate can be recycled and used to produce energy (glucose) via gluconeogenesis in the liver. The muscles cannot use lactate on their own; it must be recycled into glucose for energy use.
The purpose of the Cori cycle is to provide energy to the muscles during exercise while removing lactate and preventing lactic acidosis.
The Cori cycle is not sustainable because it costs more energy than it creates, and glycogen stores in muscles are limited.
The Cori cycle causes the recirculation of glucose back to muscle tissue for the use of energy during exercise.
Gluconeogenesis is important in the Cori cycle because lactate can be recycled and used to produce energy (glucose) via gluconeogenesis in the liver. The muscles cannot use lactate on their own; it must be recycled into glucose for energy use.
5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
National Center for Biotechnology Information.Cori cycle. PubChem Pathway Summary.
Hanson RW, Owen, OE.Gluconeogenesis.Encyclopedia of Biological Chemistry (Second Edition).2013: 381-386. https://doi.org/10.1016/B978-0-12-378630-2.00040-2
Robergs R, Ghiasvand F, Parker D.Am J of Physiol Regul Integr Comp Physiol.Biochemisty of exercise-induced metabolic acidosis.2004;287(3):502-516
Rare Disease Database.Glycogen storage disease type III.
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