Exercise Physiology Terms (Whole List)

force
That which changes or tends to change the state of rest or motion in matter (SI unit: Newton). A muscle generates force in a muscle action.

free weight
an object of known mass, not attached to a supporting or guiding structure, which is used for physical conditioning and competitive lifting

glucose
a sugar

glycogen–loading (supercompensation)
a diet or exercise-diet procedure that elevates muscle glycogen stores to concentrations two to three times normal

glycolysis
the incomplete chemical breakdwon of glycogen. In aerobic glycolysis, the end product is pyruvic acid; in anaerobic glycolysis (lactic acid system), the end produce is lactic acid.

halo effect
1) the effect (usually beneficial) that the manner, attention, and caring of a provider have on a patient during a medical encounter regardless of what medical procedures or services the encounter involves 2) the influence upon an observation of the observer’s perception of the characteristics of the individual observed (other than the characteristic under study) of the influence of the observer’s recollection or knowledge of finding on a previous occasion

Hawthorn effect
the effect (usually beneficial) of being under study upon the persons being studied; their knowledge of the study often influences their behavior

heart rate reserve
the difference between the resting heart rate and the maximal heart rate

heat exhaustion
a condition of fatigue caused by prolonged exposure to environmental heat. May be associated with headache, nausea, and vomiting.

hemoglobin (HgB)
a complex molecule found in red blood cells, which contains iron (heme) and protein (globin) and is capable of combining with oxygen

hypercapnia
presence of an abnormally large amount of CO2 in the circulating blood: increased partial pressure of CO2 resulting in extra stimulation of respiratory area

hyperlipidemia
a general term for elevated concentrations of any or all of the lipids in plasma, such as cholesterol, triglycerides and lipoproteins

hypertension
high blood pressure

hypertrophy
an increase in the size or cell of an organ

hypoglycemia
lower than normal blood sugar level due to inadequate supply or regulation; may be the result of excessive blood insulin

hypoxia
lack of adequate oxygen due to a reduced oxygen partial pressure

incidence rate
the rate at which new events occur in a population. The numerator is the number of new events that occur in a defined period; the denominator is the population at risk of experiencing the event during this period.

inotropic
force of myocardial contraction; a shift in the Frank-Starling curve to the right or to the left

insulin
a hormone secreted by the beta cells of the pancreas that causes increased cellular uptake of glucose

internal validity
the index and comparison of groups are selected and compared in such a manner that the observed differences between them on the dependent variables under study may, apart from sampling error, be attributed only to the hypothesized effect under investigation

interval training
a system of physical conditioning in which the body is subjected to short but regularly repeated periods of work stress interspersed with adequate periods of relief

intramuscular glycogen
complex carbohydrate stored within muscle cells; the glucose subunits are used as a ready source of energy for muscle metabolism

ischemic
a local and temporary deficiency of blood and oxygen, chiefly caused by narrowing of a blood vessel

kilocalorie (kcal)
a unit of work or energy equal to the amount of heat required to raise the temperature of one kilogram of water one degree Celsius

kilogram–meters (kg-m)
a unit of work

kilojoules (kJ)
a unit of energy

kinesiology
scientific study of human movement. includes such aspects of study as ex phys, motor learning/control, and biomechanics

Krebs Cycle
a series of chemical reactions occurring in mitochondria, in which carbon dioxide is produce and hydrogen ions and electrons are removed from carbon atoms (oxidation). Also referred to as the tricarboxylic acid cycle (TCA), or citric acid cycle

lactate threshold
the point during exercise where a nonlinear increase in blood lactate occurs.

lactic acid (lactate)
a fatiguing metabolite produced during anaerobic glycolysis: resulting from the incomplete breakdown of sugar or (glucose)

lactic acid system (LA system)
an anaerobic energy system in which ATP is manufactured when glucose (sugar) is broken down to lactic acid. High-intensity efforts requiring 1 to 3 minutes before energy (ATP) is primarily drawn from this system. More commonly referred to as anaerobic glycolysis.

lean body mass (weight)
the body weight minus the weight of the body fat

mass
the quantity of matter of an object that is reflected in its inertia (kilogram)

maximal aerobic consumption or power (max VO2)
the maximal rate at which oxygen can be consumed per minute; the power or capacity of the aerobic or oxygen system

maximum voluntary contraction (MVC)
the greatest force output that an individual can generate from a muscle group through only volitional control

MET (metabolic equivalent)
the amount of oxygen required per minute under resting, sitting conditions. it is approximately 3.5 mL of oxygen consumed per kg of body weight per minute

metabolic system
a system of biochemical reactions that cause the formation of waste products (metabolites) and the manufacture of ATP; for example, the ATP-PC, anaerobic glycolysis, and oxygen system

metabolism
the substance produced by metabolic action

minute ventilation
the amount of air inspired (V1) or expired (VE) in one minute, usually it refers to the expired amount

mitochondrion(a)
a subcellular structure found in all cells in which the reactions of the Krebs Cycle and electron transport system take place

motor neuron (Motorneuron)
a nerve cell, which when stimulated affects muscular contraction. Most motoneurons innervate skeletal muscle

motor unit
an individual alpha motor nerve and all the muscle fibers it innervates (to communicate nervous energy to)

muscular endurance
the ability of a muscle or muscle group to perform repeated contractions against a light load for an extended period of time

muscular strength
the force or tension that a muscle or group of muscles can exert against a resistance in one maximal effort

myoglobin
an oxygen-binding pigment similar to hemoglobin that gives the red muscle fiber its color. it acts as an oxygen store and aids in the diffusion of oxygen.

myosin-ATPase (m-ATPase)
myfibrillar adenosine triphosphate: an enzyme found in myosin that catalyzes ATP degradation to ADP and Pi; a marker for muscle fiber contraction speed

negative energy balance
a condition in which less energy (food) is taken in that is given off; body weight decreases as a result

negative work
force times distance applied in the same direction as the pull of gravity; assisted by gravity

net oxygen cost
the amount of oxygen above resting values, require to perform a given amount of work. Also referred to as net cost of exercise

neuron
a nerve cell consisting of a body (soma), with its nucleus and cytoplasm, dendrites and axon

overload principle
progressively increasing the volume of exercise during workouts over the course of the training program as fitness capacity improves

overtraining
imbalance between high volume and/or high intensity training and adequate recovery, resulting in disturbances in physical performance, biological function, and mood state

oxygen consumption
the amount or rate at which oxygen can be consumed per minute

oxygen debt
the amount of oxygen consumed during recovery from exercise, above that ordinarily consumed at rest in the same time period. there is a rapid component (alactacid) and a slow component (lactacid)

oxygen deficit
the time period during exercise in which the level of oxygen consumption is below that necessary to supply all the ATP required for the exercise; the time period during which an oxygen debt is contracted

oxygen transport system (VO2)
composed of the stroke volume (SV), the heart rate (HR), and the arterial-mixed venous oxygen difference (a-vO2 diff). mathematically, it is defined as Vo2 = SV x HR x a-vO2 diff

placebo effect
an inert medication or procedure. the placebo affect is attributable to the expectation that the regimen will have an effect, i.e., the effect is due to the power of suggestion

phosphocreatine (PC)
a chemical compound stored in muscle, which when broken down aids in manufacturing ATP

positive energy balance
a condition in which more energy (food) is taken in than is given off; body weight increases as a result

positive work
force times distance applied in opposition to the pull of gravity

power
the rate of performing work; the product of force and velocity. the rate of transformation of metabolic potential energy to work or heat (measured in watts)

prevalence rate
the total number of all individuals who have an attribute or disease at a particular time (or during a particular period) divided by the population at risk of having the attribute or disease at this point in time or midway through the period

progressive-resistance exercise (PRE)
comprehensive term to cover a wide variety of muscular strength or endurance training practices when progressive overload is emphasized

rate-pressure product
the product of heart rate and systolic blood pressure which provides a noninvasive estimate of myocardial oxygen consumption

recovery oxygen
net amount of oxygen consumed during recovery from exercise; oxygen consumed in excess of the amount consumed at rest over the same time period (reported in liters)

respiration
a cellular process where food substances are broken down to CO2 and H2 in the presence of O2 to liberate chemical energy

respiratory exchange ratio (R)
the ratio of the amount of carbon dioxide produced by the body to the amount of oxygen consumed (Vco2/Vo2)

Sliding Filament Theory
a proposed mechanism for muscle action where shortening and elongation are the result of actin protein filaments sliding inward and outward over myosin protein filaments

Slow-twitch (ST) fiber
a muscle fiber characterized by slow contraction time, low anaerobic capacity, and high aerobic capacity, all making the fiber suited for low-power output activities. AKA Type I fiber

specificity of training
principle underlying constructioin of a training program for a specific activity or skill and the primary energy system(s) involved during performance. For example, a training program for sprinters would consist of repeated bouts of sprints in order to develop both sprinting performance and the ATP-PC system

sports medicine
umbrella term that refers to all aspects of sport and exercise science, especially as used in the U.S.; examples are kinesiology, cardiac rehab, adult fitness, and athletic medicine

sprint training
a type of training system employing repeated sprints at maximal speed

steady state
pertaining to the time period during which a physiological function (such as VO2) remains at a constant (steady) value

strength
the maximal force or torque a muscle or muscle group can generate at a specific or determined velocity

stretch reflex
contraction of muscles to produce movement or tension due to muscle spindle stretch via a sharp tap on tendon or pull of gravity on skeleton

target heart rate (THR)
a predetermined heart rate to be obtained during exercise

tension
force applied to a structure that does not move; in muscle, the static or isometric tension developed with the recycling of ATP at cross-bridge sites

torque
the effectiveness of a force to overcome the rotational inertia of an object. The produce of force and the perpendicular distance from the line of action of the force to the axis of rotation (newton-meter)

total lung capacity (TLC)
volume of air in lungs at the end of maximal respiration

training
an exercise program to develop an individual for a particular event. increasing skill of performance and energy capacities are of equal consideration.

Type IA muscle fiber
commonly used classification for muscle fibers that display characteristics of slow twitch, nonfatigue, and combined oxidative and glycolytic metabolism

Type IIB muscle fiber
commonly used classification for muscle fibers that display characteristics of fast twitch, medium fatigue, and combined oxidative and glycolytic metabolism

ventilatory efficiency
the amount of ventilation required per liter of oxygen consumed (i.e. Ve/Vo2)

vital capacity (VC)
maimal volume of air forcefully expired after maximal inspiration

watt
a unit of power

weight
the force exerted by gravity on an object (SI unit: newton, traditional unit: kg) (mass=weight x acceleration due to gravity)

work
force xpressed through a displacement but with no limitation on time (joule) (Note: 1 newton x 1 meter = 1 joule)

accommodating resistance
a feature unique to isokinetic testing or training apparatus where a counter force is provided so that the speed of contraction is controlled

adenosine triphosphate (ATP)
a complex chemical compound formed with the energy released from food and stored in all cells, particularly muscles. only from the energy released by the breakdown of this compound can the cell perform work

aerobic
in the presence of oxygen

aerobic power
maximal rate at which an individual can consume oxygen during the performance of all-out, exhaustive exercise (best index of cardiorespiratory fitness)

aerobic system
term used to denote the entire series of biochemical reactions and pathways whereby ATP can be synthesized from food-fuels but only in the presence of oxygen. Includes aerobic glycolysis, Krebs Cycle, and ETS

anabolic
protein building

anaerobic
in the absence of oxygen

anaerobic glycolysis
the incomplete breakdown of carbohydrate. the anaerobic reactions in this breakdown release energy for the manufacture of ATP as they produce lactic acid (aka the lactic acid system)

anaerobic power
the development of maximal or peak power during exertion; measure as work (force in kg x distance in meters) expressed per unit of time (min)

anaerobic threshold
that intensity of work load or oxygen consumption at which anaerobic metabolism is accelerated

ATP-PC system
an anaerobic energy system in which ATP is manufactured when phosphocreatine (PC) is broken down. this system represents the most rapidly available source of ATP for use by muscle. Activities performed at maximum intensity for a period of 10 seconds or less derive ATP or energy from this system

attributal risk
the rate of a disease or other outcome in exposed individuals that can be attributed to the exposure. this measure is derived by subtracting the rate of the outcome (usually incidence or mortality) among the unexposed from the rate among the exposed individuals

beta oxidation
the series of reactions by which fat is broken down from long carbon chains to two carbon units in preparation for entry into the Krebs Cycle

bioenergetics
the study of transformations of energy in living organisms

biopsy
the removal and examination of tissue from the living body

blood pressure
the force per unit area exerted by the blood against the inside walls of an artery; the driving force that moves blood through the circulatory system

body mass index (BMI)
a much used indication of the size of an individual in relationship to his or her height; ratio of weight to height squared using units of kilograms and meters

calorie (cal)
a unit of work or energy equal to the amount of heat require to raise the temperature of one gram of water by one degree Celsius

carbohydrate
any group of chemical compounds (sugars, starches, and cellulose) contains carbon, hydrogen, and oxygen only

cardiac output (Q)
the amount of blood pumped by the heart in one minute; the produce of the stroke volume and the heart rate

cardiorespiratory endurance
the ability of the lungs and heart to take in an transport adequate amounts of oxygen to the working muscles, allowing activities that involve large muscle masses to be performed over long periods of time

comorbidity
disease(s) that coexist(s) in a study participant in addition to the index condition that is the subject of study

concentric contraction
muscle action in which the ends of the muscle are drawn closer

conditioning
augmentation of the energy capacity of muscle through a physical exercise program. conditioning is not primarily concerned with the skill of performance, as would be the case in training

diastolic blood pressure (DBP)
the lowest pressure existing in the arteries

dislipidemia
a general term for an abnormal lipid profile

eccentric contraction
muscle action in which a force external to the muscle overcomes the muscle force and the ends of the muscle are drawn further apart

electrocardiogram (ECG)
a recording of the electrical activity of the heart

electrocardiography
the making of graphic records of the variations in electrical potential caused by electrical activity of the heart muscle and detected at the body surface, as a method for studying the action of the heart muscle

endurance
the time limit of a person’s ability to maintain either an isometric force or a power level involving combinations of concentric and or/eccentric muscle actions

energy
the capability of producing force, performing work, or generating heat (joule)

energy system
one of three metabolic systems involving a series of chemical reactions resulting in the formation of waste products and the manufacture of ATP

enzyme
a protein compound that speeds up a chemical reaction

epidemiology
the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to control of health problem

ergogenic acid
any factor that improves work performance

essential hypertension
abnormally high blood pressure in humans that has no known cause and therefore no known cure; most common type of high blood pressure

exercise
any and all activity involving the generation of force by the activated muscle(s). exercise can be quantified mechanically as force, torque, work, power, or velocity of progression

exercise intensity
a specific level of muscular activity that can be quantified in terms of power (energy expenditure or work performed per unit of time), the opposing force (e.g. by free weight stack), isometric force sustained, or velocity of progression

exercise physiology
scientific study of how the body, from a functional standpoint, responds, adjusts, and adapts to acute exercise and chronic training

external validity
a study is externally valid or generalizable if it can produce unbiased inferences regarding a target population (beyond the subjects of the study). this aspect of validity is only meaningful with regard to a specified external target population

fast-twitch (FT) fiber
a muscle fiber characterized by fast contraction time, high anaerobic capacity, all making the fiber suited for high-power output activities (AKA Type II fiber)