Exphys Chapters 1-5.5 (copy)

Neuroendocrinology

The study of the interaction between the nervous system and the endocrine system, particularly how hormones affect bodily functions and responses to exercise.

Hormones

Chemical messengers released by endocrine glands that travel through the bloodstream to target tissues, influencing various physiological processes.

Lipophilic

A term describing substances, such as steroids, that have a high affinity for lipids and can easily pass through cell membranes.

Incretins

Hormones produced in the gastrointestinal tract that stimulate insulin secretion in response to food intake, particularly carbohydrates.

Gut-brain axis

The bidirectional communication network linking the gastrointestinal tract and the brain, influencing various physiological and psychological processes.

Insulin

A hormone produced by the pancreas that regulates blood glucose levels by facilitating the uptake of glucose into cells.

Sympathetic activity

The part of the autonomic nervous system that prepares the body for 'fight or flight' responses, often resulting in decreased insulin production.

Parasympathetic activity

The part of the autonomic nervous system that promotes 'rest and digest' functions, often increasing insulin production.

Plasma concentration

The amount of a substance, such as a hormone, present in the blood, which influences its physiological effects.

Receptors

Proteins on or in cells that bind to specific hormones, allowing them to exert their effects on target tissues.

Growth hormone (GH)

A hormone produced by the anterior pituitary gland that stimulates growth, cell reproduction, and regeneration in humans and other animals.

Insulin-like growth factors (IGF-1)

Hormones stimulated by growth hormone that promote growth and development, particularly in muscle and bone.

Antidiuretic hormone (ADH)

A hormone produced by the posterior pituitary gland that helps regulate water balance in the body by reducing urine output.

Thyroid-stimulating hormone (TSH)

A hormone produced by the anterior pituitary gland that stimulates the thyroid gland to produce thyroid hormones (T3 and T4).

Catecholamines

Hormones, including epinephrine and norepinephrine, produced by the adrenal medulla that are involved in the body's stress response.

Beta blockers

Medications that block the effects of epinephrine on beta-adrenergic receptors, reducing heart rate and blood pressure.

Calcium channel blockers

Medications that prevent calcium from entering cells, particularly in the heart, reducing contractility and lowering blood pressure.

Selective serotonin reuptake inhibitors (SSRIs)

A class of antidepressants that increase serotonin levels in the brain by inhibiting its reuptake, affecting mood and exercise response.

Acromegaly

A hormonal disorder resulting from excess growth hormone, leading to enlarged bones and tissues, often associated with pituitary tumors.

Exercise Metabolism

The study of how energy systems interact during exercise, including the transition from rest to exercise and recovery processes.

Energy Systems

The three primary systems (ATP-PC, glycolysis, and aerobic metabolism) that provide energy during physical activity.

Lactate Threshold

The exercise intensity at which lactate starts to accumulate in the blood, indicating a shift from predominantly aerobic to anaerobic metabolism.

Rate of Perceived Exertion (RPE)

A subjective scale (typically 6-20) used to measure the intensity of exercise based on how hard an individual feels they are working.

Oxygen Deficit

The lag in oxygen uptake at the beginning of exercise, leading to a temporary reliance on anaerobic energy systems.

Steady State

A condition during exercise where the energy supply meets the energy demand, typically reached within 1-4 minutes of starting exercise.

Excess Post-Exercise Oxygen Consumption (EPOC)

The increased rate of oxygen intake following strenuous activity, used to restore the body to its resting state.

VO2 Max

The maximum rate of oxygen consumption measured during incremental exercise, reflecting the aerobic capacity of an individual.

Glycolysis

The metabolic pathway that converts glucose into pyruvate, producing ATP and lactate when oxygen is limited.

Phosphocreatine System

An energy system that provides immediate ATP through the breakdown of phosphocreatine, primarily used during short bursts of high-intensity exercise.

Mitochondrial Density

The number of mitochondria in muscle cells, which influences the muscle's ability to utilize oxygen and produce ATP aerobically.

Anaerobic Metabolism

Energy production that occurs without oxygen, primarily through glycolysis, leading to lactate accumulation.

Aerobic Metabolism

Energy production that occurs in the presence of oxygen, utilizing carbohydrates and fats to produce ATP.

EPOC Factors

Six elements that increase oxygen consumption after exercise, including resynthesis of phosphocreatine, lactate conversion to glucose, and restoration of muscle and blood oxygen stores.

McArdle Syndrome

A genetic disorder that impairs the ability to break down glycogen, leading to exercise intolerance and muscle pain.

Respiratory Exchange Ratio (RER)

The ratio of carbon dioxide produced to oxygen consumed, used to estimate the proportion of carbohydrates and fats being utilized for energy.

Capillary Density

The number of capillaries in a given area of muscle tissue, which affects oxygen delivery and nutrient exchange during exercise.

Gluconeogenesis

The metabolic process of converting lactate back into glucose, primarily occurring in the liver post-exercise.

Fast-Twitch Muscle Fibers

Muscle fibers that are more suited for anaerobic activity and produce lactic acid more readily than slow-twitch fibers.

Bioenergetics

The processes by which the body breaks down food for energy.

Metabolism

The sum of all chemical reactions that occur in the body, including anabolic and catabolic reactions.

Anabolic Reactions

Chemical processes that build molecules and require energy.

Catabolic Reactions

Chemical processes that break down molecules and release energy.

ATP (Adenosine Triphosphate)

The primary energy carrier in cells, produced during cellular respiration.

Glycolysis

The metabolic pathway that converts glucose into pyruvate, producing ATP and NADH.

Krebs Cycle (Citric Acid Cycle)

A series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetyl-CoA.

Oxidative Phosphorylation

The process by which ATP is produced in the mitochondria using energy derived from the electron transport chain.

NADH

A high-energy electron carrier produced during glycolysis and the Krebs cycle, used in oxidative phosphorylation.

FADH2

Another high-energy electron carrier similar to NADH, produced in the Krebs cycle.

Mitochondria

Organelles known as the powerhouse of the cell, where ATP production occurs.

Anaerobic Metabolism

Energy production in the absence of oxygen, primarily through glycolysis, resulting in lactate.

Aerobic Metabolism

Energy production that requires oxygen, primarily through the Krebs cycle and oxidative phosphorylation.

Lactate

A byproduct of anaerobic metabolism, produced from pyruvate when oxygen is scarce.

Creatine Phosphate

A high-energy compound that helps regenerate ATP in muscle cells during short bursts of activity.

Substrates

The reactants in metabolic reactions, such as glucose, fatty acids, and amino acids.

Enzymes

Proteins that catalyze biochemical reactions, lowering the activation energy required for the reaction to occur.

Rate Limiting Enzymes

Enzymes that regulate the speed of a metabolic pathway, often determining the overall rate of the process.

Coupled Reactions

Reactions where an exergonic reaction drives an endergonic reaction, allowing energy transfer.

Redox Reactions

Reactions involving the transfer of electrons, where one molecule is oxidized and another is reduced.

Glycogen

A stored form of glucose, primarily found in the liver and muscles, used for energy during exercise.

Lipolysis

The breakdown of triglycerides into glycerol and fatty acids for energy production.

Gluconeogenesis

The metabolic process of synthesizing glucose from non-carbohydrate sources, such as amino acids.

Free Radicals

Unstable molecules that can damage cells, often produced during metabolic processes.

Zone Two Training

A low-intensity exercise training aimed at improving mitochondrial efficiency and fat utilization.

Apoptosis

The process of programmed cell death, which can release enzymes into the bloodstream.

Non-Alcoholic Fatty Liver Disease (NAFLD)

A condition characterized by excess fat accumulation in the liver, often linked to metabolic disorders.

Creatine Kinase

An enzyme that catalyzes the conversion of creatine phosphate to creatine, releasing energy to regenerate ATP.

Hydrogen Shuttle

A mechanism for transporting hydrogen ions and electrons into the mitochondria for ATP production.

Aerobic

A type of exercise that requires oxygen, typically associated with activities like marathon running and cross-country skiing.

Anaerobic

A type of exercise that does not require oxygen, often associated with short bursts of high-intensity activities like sprinting.

Creatine Phosphatase

An energy system used primarily during short, high-intensity efforts, such as a 100-meter dash.

Anaerobic Glycolytic

An energy system that breaks down glycogen without oxygen, typically used during strength training and activities lasting 30 seconds to 2 minutes.

VO2 Max

The maximum rate of oxygen consumption measured during incremental exercise, indicating aerobic fitness.

Absolute VO2

The total volume of oxygen consumed per minute, expressed in liters.

Relative VO2

The volume of oxygen consumed per minute per kilogram of body weight, expressed in milliliters per kilogram per minute.

Ergometer

A device used to measure work output, such as treadmills, stationary bikes, and arm bikes.

Power

The rate at which work is done, typically measured in watts (1 watt = 1 joule/second).

Work

The amount of energy used, calculated as force times distance, typically expressed in joules.

Windgate Test

A 30-second anaerobic test used to measure peak power output and anaerobic capacity.

Krebs Cycle

A series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetate derived from carbohydrates, fats, and proteins.

Efficiency

The ratio of useful work output to total energy input, often expressed as a percentage.

Direct Calorimetry

A method of measuring energy expenditure by assessing heat production in a sealed environment.

Indirect Calorimetry

A method of estimating energy expenditure by measuring oxygen consumption and carbon dioxide production.

MET (Metabolic Equivalent of Task)

A unit that estimates the amount of oxygen used by the body during physical activity, with 1 MET being the energy cost of sitting quietly.

Lactate Threshold

The exercise intensity at which lactate starts to accumulate in the blood, indicating a shift from aerobic to anaerobic metabolism.

Running Economy

The oxygen cost of running at a given speed, which improves with training and better technique.

Work Rate

The amount of work performed per unit of time, often expressed in watts.

Homeostasis

The maintenance of a constant and normal internal environment in the body.

Steady State

A condition where internal variables remain stable but are not necessarily at baseline levels, often occurring during exercise.

Mean Arterial Pressure

The average pressure in a person's arteries during one cardiac cycle, calculated as the difference between systolic and diastolic blood pressure.

Systolic Blood Pressure

The pressure of the blood as it leaves the heart when the left ventricle contracts.

Diastolic Blood Pressure

The pressure of the blood when it returns to the heart, between heartbeats.

COPD

Chronic Obstructive Pulmonary Disease, a condition that affects airflow and gas exchange in the lungs.

Negative Feedback Loop

A control mechanism that counteracts a change in a physiological variable to maintain homeostasis.

Positive Feedback Loop

A control mechanism that amplifies a change in a physiological variable, often leading to a specific outcome, such as childbirth.

Heat Shock Proteins

Proteins that help protect cells from stress and assist in the repair of damaged proteins.

Insulin

A hormone produced by the pancreas that regulates blood glucose levels by facilitating the uptake of glucose into cells.

Insulin Resistance

A condition where cells in the body become less responsive to insulin, leading to elevated blood glucose levels.

Glute4 Receptors

Insulin-sensitive glucose transporters in muscle cells that facilitate glucose uptake during exercise.

Autocrine Signaling

A form of cell signaling where a cell targets itself.

Paracrine Signaling

A form of cell signaling where a cell targets nearby cells.