"Metabolism is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the conversion of food to building blocks for proteins, lipids, nucleic acids, and some carbohydrates; and the elimination of metabolic wastes."
The processes and mechanisms by which the human body converts food into energy in order to perform physical activity.
Energy systems: The way in which the body produces and utilizes energy to perform physical tasks.
Metabolism: The biochemical reactions that take place in the body to create and break down energy.
ATP: Adenosine triphosphate, the energy currency of the body.
Aerobic vs. anaerobic exercise: Aerobic exercise focuses on training the body's oxidative system to produce ATP, while anaerobic exercise focuses on training the body's glycolytic and phosphagen systems.
VO2 max: The maximal oxygen uptake, a measure of the body's capacity to utilize oxygen.
Lactate threshold: The intensity of exercise at which lactate begins to accumulate in the bloodstream.
Substrate utilization: The way in which the body uses different energy sources, such as carbohydrates and fats, during physical activity.
Energy expenditure: The amount of energy the body uses during physical activity, including both aerobic and anaerobic metabolism.
Exercise intensity: The level of effort required to perform a physical activity, typically measured in terms of heart rate or perceived exertion.
Energy balance: The relationship between energy intake and energy expenditure, which can impact overall health and fitness.
Stroke volume: The amount of blood the heart pumps with each beat, which can impact aerobic capacity.
Muscle fiber types: The different types of muscle fibers in the body, including slow-twitch and fast-twitch fibers, which can impact the type of exercise someone should perform.
Oxygen uptake kinetics: The time it takes for the body to adjust oxygen uptake during exercise.
Respiratory exchange ratio: The ratio of carbon dioxide production to oxygen uptake, which can provide information about substrate utilization during exercise.
Energy stores: The various areas in the body where energy is stored, such as muscle glycogen and fat stores.
ATP-PCr system: This system provides energy for short bursts of high-intensity activity, such as weightlifting or sprinting. It uses creatine phosphate to quickly produce ATP.
Anaerobic glycolysis: This system provides energy for longer periods of high-intensity activity, such as high-intensity interval training. It breaks down glucose without oxygen to produce ATP.
Aerobic glycolysis: This system provides energy for lower-intensity exercise, such as jogging or cycling. It breaks down glucose with oxygen to produce ATP.
Lipolysis: This system provides energy for low-intensity exercise that lasts for longer periods of time, such as distance running or hiking. It uses stored fat to produce ATP.
Oxidative phosphorylation: This system provides energy for long-duration exercise, such as endurance events like marathons. It breaks down glucose, fat, and protein with oxygen to produce ATP.
Anaerobic Alactacid system: This system provides short-term energy to power explosive movements, such as jumping or throwing, without producing lactic acid.
Aerobic system: This system utilizes oxygen to produce ATP and fuels long-term exercise such as distance running.
Phosphagen system: This system utilizes stored ATP and creatine phosphate (CP) in the muscles to produce energy rapidly for brief, high-intensity exercise.
Lactic acid system: This system is used during intense exercise when the body can’t provide enough energy to keep up with the demand. It produces ATP when the oxygen supply is low, but it comes with a high cost of lactic buildup that leads to muscle fatigue.
Mitochondrial system: This system is responsible for producing ATP from the movement of electrons, which is formed during the oxidation of carbohydrates, amino acids, and fatty acids.
Krebs cycle: It is a series of biochemical reactions that occur in the mitochondria and produce energy required for moderate-intensity exercises in the form of ATP.
Beta-oxidation system: This system breaks down fatty acids to form acetyl-CoA and produce ATP that is used in the Krebs cycle.
Cytoplasm system: This system is used to process glucose and combine it with oxygen for ATP production in the cytoplasm.
Cori cycle: It is a metabolic process that takes place in the liver and muscles, producing glucose from lactate produced in the muscles during intense exercise.
Deamination system: This system breaks down amino acids into ATP, which is used to provide energy for low-intensity activities.
"Metabolic reactions may be categorized as catabolic – the breaking down of compounds (for example, of glucose to pyruvate by cellular respiration); or anabolic – the building up (synthesis) of compounds (such as proteins, carbohydrates, lipids, and nucleic acids)."
"Enzymes are crucial to metabolism because they allow organisms to drive desirable reactions that require energy and will not occur by themselves, by coupling them to spontaneous reactions that release energy."
"Enzymes act as catalysts – they allow a reaction to proceed more rapidly – and they also allow the regulation of the rate of a metabolic reaction, for example in response to changes in the cell's environment or to signals from other cells."
"The chemical reactions of metabolism are organized into metabolic pathways, in which one chemical is transformed through a series of steps into another chemical, each step being facilitated by a specific enzyme."
"The metabolic system of a particular organism determines which substances it will find nutritious and which poisonous."
"The basal metabolic rate of an organism is the measure of the amount of energy consumed by all of these chemical reactions."
"These similarities in metabolic pathways are likely due to their early appearance in evolutionary history, and their retention is likely due to their efficacy."
"In various diseases, such as type II diabetes, metabolic syndrome, and cancer, normal metabolism is disrupted."
"The metabolism of cancer cells is also different from the metabolism of normal cells, and these differences can be used to find targets for therapeutic intervention in cancer."
"Metabolism (, from Greek: μεταβολή metabolē, 'change')."
"Usually, catabolism releases energy, and anabolism consumes energy."
"These enzyme-catalyzed reactions allow organisms to grow and reproduce, maintain their structures, and respond to their environments."
"The word metabolism can also refer to the sum of all chemical reactions that occur in living organisms, including digestion and the transportation of substances into and between different cells, in which case the above described set of reactions within the cells is called intermediary (or intermediate) metabolism."
"The elimination of metabolic wastes."
"Enzymes allow organisms to drive desirable reactions that require energy and will not occur by themselves, by coupling them to spontaneous reactions that release energy."
"Metabolic pathways are important because they allow chemical transformation through a series of steps, each facilitated by a specific enzyme."
"For example, some prokaryotes use hydrogen sulfide as a nutrient, yet this gas is poisonous to animals."
"The conversion of food to building blocks for proteins, lipids, nucleic acids, and some carbohydrates."
"The differences in metabolism between cancer cells and normal cells can be used to find targets for therapeutic intervention in cancer."