The body faces a catabolic state during normal metabolic functions. This idea, opposed to an anabolic state, actually defines the breakdown of foods and nutrients so that they will later have the ability to build up and add to the muscle or tissue growth process.
Catabolic exercises are largely aerobic, meaning they consume oxygen, and help burn calories and fat. The use of oxygen is a key factor in catabolism, as oxygen is a reducing agent in many chemical processes. Typical catabolic/aerobic exercises are jogging, cycling, swimming, dancing or any physical activity done for at least 20 minutes at moderate intensity. Time is a major factor in getting results because after about 15-20 minutes, the body switches from using glucose and glycogen to using fat to sustain the energy requirements of the body. For that catabolic process, oxygen is required. By combining aerobic and anaerobic exercises on a consistent basis, a person can use anabolic and catabolic processes to reach or maintain an ideal body weight as well as improve and sustain overall health.
Anabolic processes use simple molecules within the organism to create more complex and specialized compounds. This synthesis, the creation of a product from a series of components, is why anabolism is also called “biosynthesis.” The process uses energy to create its end products, which the organism can use to sustain itself, grow, heal, reproduce or adjust to changes in its environment. Growing in height and muscle mass are two basic anabolic processes. At the cellular level, anabolic processes can use small molecules called monomers to build polymers, resulting in often highly complex molecules. For example, amino acids (monomers) can be synthesized into proteins (polymers), much like a builder can use bricks to create a large variety of buildings.
Catabolic processes break down complex compounds and molecules to release energy. This creates the metabolic cycle, where anabolism then creates other molecules that catabolism breaks down, many of which remain in the organism to be used again.
The principal catabolic process is digestion, where nutrient substances are ingested and broken down into simpler components for the body to use. In cells, catabolic processes break down polysaccharides such as starch, glycogen, and cellulose into monosaccharides (glucose, ribose and fructose, for example) for energy. Proteins are broken down into amino acids, for use in anabolic synthesis of new compounds or for recycling. And nucleic acids, found in RNA and DNA, are catabolized into nucleotides as part of the body’s energy needs or for the purpose of healing.
The Catabolic Idea
By defining the catabolic state within the human body, avid fitness enthusiasts have the ability to achieve their goals more easily. For example, by knowing that muscles actually endure a break down phase because of hormones released during each workout, you have the ability to counteract this phenomenon by consuming high-quality nutrient sources before, during or after your exercise sessions.
In the most basic written form, the catabolic process involves anything and everything that naturally occurs or induces the breakdown of larger molecules into several smaller building blocks. These separate parts eventually combine in a process known as anabolism, which greatly benefits muscle tissue growth.
Both catabolism and anabolism work together naturally in the human body in order to maintain a healthy energy level and durable, functional muscle tissue. However, before any muscle gains the ability to benefit from these two major processes, simple scientific factors have to take their proper course.
The Catabolic Process
When food enters the body, from the very first moment, larger sized molecules naturally become smaller. The idea of digestion actually implies catabolism. Once food particles break down into smaller nutrients, these chemical strains that once composed the larger nutrient molecules release energy through an oxidation process.
The catabolic process releases energy that works to help maintain proper muscle activity. The oxidation process that occurs during catabolism helps synthesize the necessary chemical building blocks that adenosine triphosphate (ATP). Multiple ATP molecules give cells the power to transfer more energy produced during the catabolic process to the anabolic process.
In basic terms, catabolism acts as the sole energy provider for the proper preservation and growth in nearly all cells.
Importance of Catabolism
Aside from helping fuel the human body with energy that’s necessary to grow and function, catabolism sometimes acts as a negative process that leads to adverse health effects. This does not occur often, but when the body has an extremely high rate of catabolism, as opposed to anabolism, muscle tissue and essential fat deposits found within the body become depleted.
For example, during rest, the body tends to recover and remain in an anabolic state. When the body does not properly rest for long periods of time, as in prolonged vigorous exercise, muscle tissue will continue to break down. Without proper nutritional intake, the natural process of tissue growth and repair will not take place.
Catabolism is the set of metabolic pathways that breaks down molecules into smaller units that are either oxidized to release energy, or used in other anabolic reactions. Catabolism breaks down large molecules (such as polysaccharides, lipids, nucleic acids and proteins) into smaller units (such as monosaccharides, fatty acids, nucleotides, and amino acids, respectively).
Cells use the monomers released from breaking down polymers to either construct new polymer molecules, or degrade the monomers further to simple waste products, releasing energy. Cellular wastes include lactic acid, acetic acid, carbon dioxide, ammonia, and urea. The creation of these wastes is usually an oxidation process involving a release of chemical free energy, some of which is lost as heat, but the rest of which is used to drive the synthesis of adenosine triphosphate (ATP). This molecule acts as a way for the cell to transfer the energy released by catabolism to the energy-requiring reactions that make up anabolism. (Catabolism is seen as destructive metabolism and anabolism as constructive metabolism). Catabolism therefore provides the chemical energy necessary for the maintenance and growth of cells. Examples of catabolic processes include glycolysis, the citric acid cycle, the breakdown of muscle protein in order to use amino acids as substrates for gluconeogenesis, the breakdown of fat in adipose tissue to fatty acids, and oxidative deamination of neurotransmitters by monoamine oxidase.
There are many signals that control catabolism. Most of the known signals are hormones and the molecules involved in metabolism itself. Endocrinologists have traditionally classified many of the hormones as anabolic or catabolic, depending on which part of metabolism they stimulate. The so-called classic catabolic hormones known since the early 20th century are cortisol, glucagon, and adrenaline (and other catecholamines).
In recent decades, many more hormones with at least some catabolic effects have been discovered, including cytokines, orexin (also known as hypocretin), and melatonin.
Many of these catabolic hormones express an anti-catabolic effect in muscle tissue. One study found that the administration of epinephrine (adrenaline) had an anti-proteolytic effect, and in fact suppressed catabolism rather than promoted it. Another study found that catecholamines in general (the main ones being, epinephrine, norepinephrine and dopamine), greatly decreased the rate of muscle catabolism.
Catabolic hormones include:
- Adrenaline: Also called “epinephrine,” adrenaline is produced by the adrenal glands. It is the key component of the “fight or flight” response that accelerates heart rate, opens up bronchioles in the lungs for better oxygen absorption and floods the body with glucose for fast energy.
- Cortisol: Also produced in the adrenal glands, cortisol is known as the “stress hormone.” It is released during times of anxiety, nervousness or when the organism feels prolonged discomfort. It increases blood pressure, blood sugar levels and suppresses the body’s immune processes.
- Glucagon: Produced by the alpha cells in the pancreas, glucagon stimulates the breakdown of glycogen into glucose. Glycogen is stored in the liver and when the body needs more energy (exercise, fighting, high level of stress), glucagon stimulates the liver to catabolize glycogen, which enters the blood as glucose.
- Cytokines: This hormone is a small protein that regulates communication and interactions between cells. Cytokines are constantly being produced and broken down in the body, where their amino acids are either reused or recycled for other processes. Two examples of cytokines are interleukin and lymphokines, most often released during the body’s immune response to invasion (bacteria, virus, fungus, tumor) or injury.
Foods with very high water content, such as celery, also have this tiny catabolic effect. But the nutritional value of water and celery are not high enough to properly sustain an organism, so relying solely on these foods to lose weight can lead to serious health complications