Glossary of Terms

Adaptation (in sport) – changes occur at structural and physiological levels in response to repeated bouts of physical exercise

Adenosine Triphosphate, (ATP) – energy-carrying molecule found in the cells of all living things. ATP captures chemical energy obtained from the breakdown of food molecules and releases it to fuel other cellular processes.

Aerobic – processes with utilization of oxygen

Aerobic Endurance – the ability to maintain specific level of intensity (by speed, power) which is supported predominantly by the usage of oxygen as the main source of energy production

Aerobic Power – the absolute maximum level of oxygen the athlete can consume in a unit of time (usually measured in one minute). This is often also referred to as maximal oxygen uptake, or maximal oxygen consumption.

Alactic Oxygen Debt – the part of oxygen debt that is not accompanied by an increase of lactic acid in blood

Amino-Acids – chemical compounds in body that are building blocks of proteins

Anaerobic – processes without oxygen participation

Anaerobic Capacity – the ability to maintain a specific level of intensity (by speed, power) or repetitions of efforts close to maximum, which are supported predominantly by anaerobic mechanisms (without use of oxygen) as the main source of energy production

Anaerobic Power – the maximum amount of energy or work produced without additional contribution of aerobic energy producing mechanisms (without utilization of oxygen)

Anaerobic Threshold – the maximum level of exercise intensity which is supported by aerobic energy mechanisms and borders with anaerobic energy production through glycolysis leading to the rapid accumulation of lactic acid in blood

Androgen – a class of hormones associated with masculine development

Anuria – absence of urine production

Ascorbic Acid – vitamin C

Atrophy – reduction of size and loss of cells and tissues

Auto Regulation – the regulation of blood flow to an organ or tissue by direct effects of localized changes of chemicals or temperature in the organ or tissue

Beta Oxidation Cycle – a series of metabolic reactions in which fatty acids are broken down for energy

Biopsy – a surgical extraction (usually by a needle) of tissue samples for further analysis

Blood Doping – the practice of injecting previously withdrawn and stored at cold temperatures blood cells with a goal to increase the number of circulating red blood cells

Body Composition – the proportion of fat and lean masses of the human body

Body Density – the weight of the body per unit volume (typically in grams per cubic centimeter)

Bradycardia – decreased heart rate, especially in rest. Often connected with inability to reach higher heart rates in high intensity exercises.

Calorie – a unit of energy required to raise the temperature of a kilogram of water by 1 degree of Celsius under specified conditions (also known as kilocalorie)

Carbohydrate – a chemical compound consisting of carbon, hydrogen and oxygen atoms in specified arrangements. Carbohydrates are found in foods such as bread, potatoes, pasta, and rice.

Cardiac – pertaining to the heart

Cardiac Output – the volume of blood pumped from a ventricle to the heart per unit of time.  Cardiac output is a combination of heart rate and stroke volume.

Cardiorespiratory Endurance – see aerobic endurance

Cardiovascular – pertaining to the heart and blood vessels

Catabolism – the degradation of complex substances into simpler structures (e.g. the breakdown of fats and carbohydrates into energy)

Central Nervous System – the brain and spinal cord

Citric Acid Cycle – Krebs cycle

Coenzyme – a non-protein molecule that is required in enzyme-catalyzed reactions

Collagen – a fibrous protein that serves as the major component of ligaments and tendons

Conduction – the transfer of heat energy by direct physical conduct

Continuous Work / Effort – exercise which is not interrupted by rest pauses.

Core Temperature – the temperature of the deep muscles and viscera of the body

Cortisol – a hormone secreted by the adrenal cortex. Cortisol results in conservation of carbohydrate stores in the body at the expense of fat and protein.

Creatine Phosphate – a chemical that can donate its phosphate molecule to adenosine diphosphate to rapidly replenish tissue stores of adenosine-tri-phosphate

Cytochromes – proteins in the electron transport system of mitochondria

Dehydration – a condition resulting from excessive body water loss

Distole – relaxation of the heart

Diffusion – the movement of chemicals such as oxygen, carbon dioxide, sodium and calcium from an area to another (from high concentration to lower)

Electrocardiogram (EKG, ECG) – a recording of the transmission of an action potential through the heart

Electrolyte – any substance that dissociates into positively and negatively charged ions when dissolved in water

Energy – power derived from the utilization of physical or chemical resources

Endurance – the ability to maintain work for a prolong period of time, especially despite fatigue. Also used as “stamina”.  Can be viewed as a rate of utilization of available resources.

Enzyme – a protein molecule that serves as a catalyst for biochemical reactions

Erythropoietin – a hormone secreted by kidneys. Stimulates the bone marrow cells to produce red blood cells.

Estrogen – a class of hormones associated with feminine development

Fast Twitch Fibers – skeletal muscle fibers most active in short duration, intensive exercise (sprints, jumps)

Fatigue – condition caused by excessive physical exercise resulting in diminishing performance. Different levels of fatigue exists, from “ordinary” (one-day exercise) to clinical (permanent damage caused by regular fatigue).

Fatty Acids – long-chain organic acids associated with glycerol in fat molecules. Fatty acids are used extensively for muscular fuel, especially in prolonged exercise (with presence of oxygen – aerobic).

Flexibility – the range of motion of the body’s joints

Free Fatty Acids – fatty acids that circulate in the blood and are only loosely attached to proteins. Free fatty acids are used extensively for energy production (aerobic) in long-duration exercise.

Glucagon – a hormone secreted by pancreas. Glucagon causes more glucose to be released from liver into blood.

Glucose – blood sugar

 Glycogen – a polymer of glucose. Glycogen is the storage form of carbohydrates.

 Glycogen Loading – the filling of liver and muscle glycogen stores to greater than normal levels by consumption of a high carbohydrate diet following depletion of glycogen stores through exhaustive exercise

 Glycogen Super Compensation – See Glycogen loading

Glycogen Phosphorylate – an enzyme involved in the breakdown of glycogen

Glycolysis – the breakdown of glucose to pyruvic or lactic acid.  Also, sometimes used to describe the breakdown of glucose to carbon dioxide and water.

Growth Hormone – a hormone released from anterior pituitary. Causes growth of many body cells.

Heat Cramps – muscle cramps associated with heat-induced changes in electrolyte balance in muscle tissue. May be relieved with some consumption of salted water.

Heat Exhaustion – extreme condition of fatigue, collapse, or fainting caused by heat-induced reduction in cardiac output

Hematocrit – the percentage of blood volume that is made up of red blood cells

Hemoglobin – a protein found in red blood cells. Hemoglobin is associated with the ability to capture and deliver oxygen to working muscles.

Homeostasis – the tendency of the body to maintain its internal environment within narrow ranges of temperature, acidity, osmolality, etc. Also relates to body tendency to adjust its requirements in relation to external environment and re-adjust them once such conditions are removed.

Hyperplasia – increased cell count

Hypertrophy – increased cell size leading to increased tissue size

Hyperventilation – high rate of ventilation that exceeds physiological demand

Hypo Kinesis – relative lack of physical activity

Intermittent Exercise – exercise sessions interrupted by rest

Interval Exercise – repetitive bouts of work (2-10 minutes each) interrupted by relatively short periods of rest (10-40 seconds, and no longer than 1 minute)

Ischemia – a lack of blood flow

Isokinetic Contraction – a muscular contraction through a range of motion at constant (fixed) velocity

Isometric (static) Contraction – a muscular contraction in which there is no change in angle of the involved join(s) and little or no change in the length of the contracting muscles

Isotonic Contraction – a muscular contraction in which a constant load is moved through a range of motion in the involved joints.

Joule – a unit of measurement of energy (1 kilo joule equals approximately 4.2 kilocalories)

Karvonen Formula – a formula for prescribing exercise heart rate.  Originally introduced for fitness purposes but is often used in sport, for which it was not intended.

Lactic Acid (lactate) – the end-product of anaerobic glycolysis

Lactic Acid Oxygen Debt – the portion of the oxygen debt that is associated with increased levels of blood lactate

Maximal Oxygen Uptake (also maximal oxygen consumption, VO2 max, maximal aerobic power) – the greatest volume of oxygen used by the cells of the body per unit of time

Mitochondria – the structure located within the cells. Mitochondria contain the enzymes responsible for the generation of adenosine triphosphate by aerobic mechanisms.

Myofibril – element of muscle which contains the contractile actin and myosin proteins

Myoglobin – oxygen-binding protein in skeletal muscle

Net Caloric Cost of Exercise – the amount of oxygen consumed during both exercise and recovery, less the oxygen that would have been consumed had the subject remained at rest during the period of exercise and recovery

Neural Pathways – a response or adaptation that involves changes in nerve activity

Neuron – a nerve cell consisting of cell body, axon, and dendrites

Newton (N) – the force that imparts an acceleration of one meter per second on a mass of one kilogram

Obesity – excess body fat

Oxidation – the removal of electrons from a chemical

Oxidative Phosphorylation – the production of adenosine triphosphate, dependent upon oxidative processes in the electron transport system of the mitochondria

Oxygen Debt – the amount of oxygen required to offset and remove the elements accumulated during the exercise

Oxygen Deficit – the difference between theoretical oxygen requirement of a physical activity and the oxygen actually used during the activity

Oxygen Uptake – the oxygen used up by the mitochondria in all the body’s cells.

Power – work performed per unit of time.

Pyruvic Acid – a three carbon molecule produced by the breakdown of glycogen or glucose

Response – an immediate temporary adjustment in physiological function brought on by a single effort or exercise, usually manifesting in increased heart rate, etc.

Rest (recovery) Intervals – the periods of recovery between repetitions in different exercise types. Rest can be Active or Passive.

Parametric Training –  is a training program in which the athlete works on improving one variable at a time (speed, duration of exercise, etc.) while keeping other variables open. Variables are labeled as “parameters”.

 Slow-Twitched Fibers – skeletal muscle fibers characterized by relatively slow contraction times and great capacity for the aerobic production of adenosine tri-phosphate

 Steady State – the state of physiological stability in which energy demands can be met predominantly by aerobic processes for a prolonged periods of time (usually over 20-30 minutes of work)

 Stroke Volume – the amount of blood pumped out of the heart ventricles with each beat

 Submaximal Exercise – usually exercise at less than maximal intensity, but also refers to exercise of less them maximal duration. Submaximal exercise is usually associated with repetitive type of exercisers.