Editor: Brian R MacIntosh

Open Textbook of Exercise Physiology

This site provides the first set of Glossary Terms for the Open Textbook of Exercise Physiology.

Open Textbook of Exercise Physiology

The Open Textbook of Exercise Physiology is an Online Textbook, free for anyone to consult.  At this time, the book is scheduled to be released In July, 2023.  Below is the Table of Contents

Scroll down for definitions of words and expressions commonly used in exercise physiology

  1. Glossary for OTEP

    This site displays the words that are available in the glossary of the Open Textbook of Exercise Physiology

Glossary for the Open Textbook of Exercise Physiology

contraction (noun):

Contractile tissue includes the heart, skeletal muscles blood vessels and gut. when activated, contractile tissue will undergo contraction. This means that myosin will interact with actin, and ATP will be split to form ADP and Pi. This will result in force development and/or shortening.  

convection (noun):

heat loss to the environment can occur by convection. This is when the substance immediately around you is constantly replaced, such as when the wind is blowing and the air that you warmed by conduction is replaced. Convection allows continuous heat loss (or gain if you are in a hot-tub). Wikipedia

convective (adjective):

relating to flow or movement; 

convergence

coming together. several sources come together to form fewer streams. Convergence in neural physiology refers to input from several neurons connecting with a common target neuron. In the vascular system, convergence would be several blood vessels joining to allow their flow to go through fewer vessels. The opposite of convergence is divergence.

coronary heart (artery) disease:

vascular disease of the coronary vessels. Vascular disease typically means a build-up of plaque and calcification in the internal wall of vessels, particularly arteries. This progresses to thickening of the smooth muscle layer and restriction of the lumen. When blood flow is restricted, relative ischemia can occur. This ischemia is detected as pain, known as angina. NIH

correlation (noun):

a measure of the strength of the relationship or interdependence between two variables. A correlation tells you how closely two variables or measurements change in tandem. Wikipedia

corticosteroid (noun):

a class of steroid hormone, secreted by the adrenal cortex, that has effects on glucose and electrolyte balance including glucocorticoid, cortisol, and aldosterone. Wikipedia

cortisol (noun):

one of the corticosteroid hormones secreted by the adrenal cortex. Cortisol is released when the body is under stress or when blood glucose is decreased. One of the key functions of cortisol is to increase gluconeogenesis by promoting protein catabolism, making amino acids available to the liver for synthesis of new glucose. Wikipedia

C-reactive protein (CRP):

a specific protein produced by the liver that circulates in the blood and increases in concentration during an inflammatory response.  CRP is an acute-phase protein and is often used to detect an immune response in the body.  Wikipedia

creatine (noun):

a small nitrogen-containing molecule that when bound with phosphate can serve as an immediate supply of energy, transferring the phosphate to ADP to form ATP. Creatine is a popular supplement for strength training athletes and is used in therapy for several pathologies. Wikipedia

creatine kinase (CK)

an enzyme that catalyzes the reaction: ADP + Creatine phosphate  <=>  ATP + Creatine. A kinase always transfers a phosphate between molecules. There are two isoforms of CK; one located in the membrane of the mitochondria which favours the above reaction to the left (forming creatine phosphate) and one in the myofibrils that favours the above reaction to the right, forming creatine.  

also known as creatine phosphokinase

creatine phosphate

a high energy phosphate molecule that serves to buffer ATP concentration by the creatine kinase reaction.  Creatine, formed in the myofibrils can diffuse to the intermyofibrillar mitochondria where creatine kinase removes a phosphate from ATP, giving it to creatine, forming creatine phosphate. This newly formed creatine phosphate can diffuse to the myofibril.  This movement of creatine and creatine phosphate is referred to as the creatine shuttle.

 

available

creatinine

a breakdown product of creatine. A very small proportion of creatine is converted to creatinine each day. The kidneys dispose of creatinine by filtration, without further exchange in the distal convoluted tubules. Therefore, measurement of creatinine in the blood and urine allows estimation of the glomerular filtration rate. 

costamere (noun):

a unique feature of skeletal muscle is that adjacent cells are linked at recurring structures called costameres. The costameres join myofibrils at the Z-disk and extend into the connective tissue around each cell (endomysium) to connect with adjacent myocytes at their Z-disk. The costameres align myofibrils and myocytes to give skeletal and cardiac muscle a striated appearance because the sarcomeres are aligned.

critical power:

the asymptote of the relationship between power and endurance, obtained by completion of at least three time-trials selected in anticipation of completion in 3 to 15 min. This power output is thought to represent the highest intensity of exercise that can be sustained by aerobic metabolism. Critical power can also be determined as the slope of the relationship between work and endurance in the same time-trials. See critical speed.  

critical speed (CS):

the asymptote of the relationship between speed and endurance, obtained by completion of at least three time-trials selected in anticipation of completion in 3 to 15 min. This speed is thought to represent the highest intensity of exercise that can be sustained exclusively by aerobic metabolism. See critical power.  

cross-bridge (noun)

when the myosin head binds to actin, it forms a cross-bridge. This binding between actin and myosin initiates release of inorganic phosphate (Pi) and results in a conformational change to the myosin configuration that causes force generation and/or motion. The myosin head is the molecular motor of muscle function.

cross-bridge theory:

proposed by A.F. Huxley, the cross-bridge theory explains how muscle contraction occurs. The general idea is that projections off the myosin (thick) filaments indepedently interact with the actin (thin) filaments and pull these filaments towards the middle of the sarcomere when the muscle is activated.

cross-bridge turnover:

a measure of the rate of cycling of cross-bridges. The units would be s-1, indicating the number of unitary cross-bridge cycles per second.  

cross-reinnervation (noun):

a classical experimental approach to demonstrate the capability of changing fibre type within a muscle. In this animal study, the nerve of one muscle is cut and inserted into a muscle of different fibre type. Complete cross-reinnervation would involve also cutting the nerve of the second muscle and inserting it into the first muscle. The animal is allowed to recover, and the contractile properties of the experimental muscles are evaluated, revealing that they have changed fibre-type composition.  

cross-sectional studies:

physical activity and health variables are measured at the same point in time across different populations of subjects and the researchers examine whether the variables are related or vary between the populations.

crossed extensor reflex

a reflex extension that originates from sensory input from the opposite side. The reflex typically results in leg extension when the opposite leg experiences pain. The end result of this action is withdrawal from the pain-inducing stimulus while allowing support of the body by the opposite limb.

current

the rate at which charged particles moves along a specific path, or past a certain location. 

curve-fitting (noun):

finding the appropriate constants for an equation that allows a close fit of the line described by an equation and the pattern shown by two variables. Typically, curve-fitting will be done by the method of least squares. That is, a variety of values for the constants will be tested and the values that give the smallest discrepancy (squared) between the actual measured values. Wikipedia

cytokine (noun):

small molecules released from various tissues and having regulatory function on the same tissue or other tissues.  For example, muscle can release cytokines that affect muscle growth and development, but also can effect nerve changes

cytoplasm:

the fluid/gelatinuous contents of a cell, excluding the nucleus.

cytoskeleton (noun):

an internal frame, like that for a tent, but for individual cells.  The cytoskeleton is formed with several proteins including actin, actinin, desmin, dystrophin and many more. Cytoskeletal proteins participate in several cellular functions, including: giving the cell shape, allowing motion, cell division, mechanical transduction and force transfer.