Essentials of Exercise Science (Glossary) Flashcards
Abduction
Movement away from the midline of the body.
Absorption
The uptake of nutrients across a tissue or membrane by the gastrointestinal tract.
Acceptable Macronutrient Distribution Range (AMDR)
The range of intake for a particular energy source that is associated with reduced risk of chronic disease while providing intakes of essential nutrients.
Acetyl coenzyme A (acetyl-CoA)
An important molecule in metabolism, used in many biochemical reactions. Its main use is to convey the carbon atoms within the acetyl group to the citric acid cycle to be oxidized for energy production. This compound forms the common entry point into the Kreb’s cycle for the oxidation of carbohydrate and fat.
Acetylcholine
A white crystalline neurotransmitter and derivation of choline that is released at the ends of nerve fibers in the somatic and parasympathetic nervous systems and is involved in the transmission of nerve impulses in the body.
Acromioclavicular (A/C) joint
The junction of the acromion process of the scapula with the distal clavicle.
Actin
Thin contractile protein in a myofibril.
Active isolated stretching (AIS)
A stretching technique modeled after traditional strength-trianing workouts. Stretches are held very briefly in sets of a specified number of repetitions, with a goal of isolating an individual muscle in each set.
Activities of daily living (ADL)
Activities normally performed for hygiene, bathing, household chores, walking, shopping, and similar activities.
Adduction
Movement toward the midline of the body.
Adenosine diphosphate (ADP)
One of the chemical by-products of the breakdown of adenosine triphosphate (ATP) during muscle contraction
Adenosine monophosphate (AMP)
Substance found in muscle cells that participates in energy released by working muscle.
Adenosine trisphosphate (ATP)
A high-energy phosphate molecule required to provide energy for cellular function. produced both aerobically and anaerobically and stored in the body.
Adequate intake (AI)
A recommended nutrient intake level that, based on research, appears to be sufficient for good health.
Adipocyte
A fat cell.
Adipose tissue
Fatty tissue; connective tissue made up of fat cells.
Adrenocorticotropin hormone (ACTH)
A hormone released by the pituitary gland that affects various important bodily functions; controls the secretion in the adrenal gland of hormones that influence the metabolism of carbohydrates, sodium, and potassium; also controls the rate at which substance are exchanged between the blood and tissues.
Aerobic
In the presence of oxygen.
Aerobic glycolysis
A metabolic pathway that requires oxygen to facilitate the use of glycogen for energy (ATP)
Afterload
The pressure in the aorta and pulmonary trunk, respectively, that the left and right ventricles of the heart must overcome to eject blood.
Agonist
The muscle directly responsible for observed movement; also called the prime mover.
Aldosterone
One of two main hormones released by the adrenal cortex; plays a role in limiting sodium excretion in the urine.
All-or-none principle
The principle of muscle contraction that states that when a motor unit is activated, all of the muscle fibers will maximally contract.
Allergen
A substance that can cause an allergic reaction by stimulating type-1 hypersensitivity in atopic individuals.
Alpha cells
Endocrine cell in the islets of Langerhans of the pancreas responsible for synthesizing and secreting the hormone glucagon, which elevates the glucose levels in the blood
Alveoli
Spherical extensions of the respiratory bronchioles and the primary sites of gas exchange with the blood
Alzheimer’s disease
An age-related, progressive disease characterized by death of nerve cells in the brain leading to a loss of cognitive function; the cause of the nerve cell death is unknown.
Amenorrhea
The absence of menstruation.
Amino acids
Nitrogen-containing compounds that are the building blocks of protein.
Anabolic
Muscle-building effects.
Anaerobic
Without the presence of oxygen
Anaerobic glycolysis
The metabolic pathway that uses glucose for energy production without requiring oxygen. Sometimes referred to as the lactic acid system or anaerobic glucose system, it produces lactic acid as a by-product.
Anaerobic threshold (AT)
The point during high-intensity activity when the body can no longer meet its demand for oxygen and anaerobic metabolism predominates. Also called lactate threshold.
Anatomical position
Standing erect with the feet and palms facing forward.
Androgenic Effects
related to developing masculine characteristics associated with manhood.
Anemia
A reduction in the number of red blood cells and/ or quantity of hemoglobin per volume of blood below normal values.
Angina
A common symptom of coronary artery disease characterized by chest pain, tightness, or radiating pain resulting from a lack of blood flow to the heart muscle.
Anorexia nervosa
An eating disorder characterized by refusal to maintain body weight of at least 85% of expected weight; intense fear of gaining weight or becoming fat; body-image disturbance, including a disproportionate influence of body weight on self-evaluation; in women, the absence of at least three consecutive menstrual periods.
Antagonist
The muscle that acts in opposition to the contraction produced by an agonist (prime mover) muscle.
Antidiuretic hormone (ADH)
A hormone released by the posterior pituitary gland during exercise; reduces urinary excretion of water and prevents dehydration.
Antioxidant
A substance that prevents or repairs oxidative damage; includes vitamins C and E, some carotenoids, selenium, ubiquinones, and bioflavonoids.
Anus
The end point of the gastrointestinal tract through which semisolid waste is passed from the body.
Anxiety
A state of uneasiness and apprehension; occurs in some mental disorders.
Aorta
The major artery of the cardiovascular system; arises from the left ventricle of the heart.
Aponeurosis
A white, flattened, tending us expansion that mainly serves to connect a muscle to the parts that it moves.
Applied force
An external force acting on a system (body or body segment).
Arterial-mixed venous oxygen difference (a-vO2 difference)
The difference in oxygen content between arterial and mixed venous blood, which reflects the amount of oxygen removed by the whole body.
Arterioles
Small-diameter blood vessels that extend and branch out from an artery and lead to capillaries; the primary site of vascular resistance.
Arteriosclerosis
A chronic disease in which thickening, hardening, and loss of elasticity of the arterial walls result in impaired blood circulation; develope with aging, and in hypertension, diabetes, hyperlipidemia, and other conditions.
Artery
A blood vessel that carries oxygenated blood away from the heart to vital organs and the extremities.
Arthritis
Inflammation of a joint; a state characterized by the inflammation of joints.
Articulation
A joint.
Asthma
A chronic inflammatory disorder of the airway that affects genetically susceptible individuals in response to various environmental triggers such as allergens, viral infection,exercise, cold, and stress.
Atherosclerosis
A specific form of arteriosclerosis characterized by the accumulation of fatty material on the inner walls of the arteries, causing them to harden, thicken, and lose elasticity.
Atria
The two upper chamber of the heart (right and left atrium)
Atrioventricular node (AV node)
The specialized mass of conducting cells in the heart located at the atrioventricular junction.
Atrophy
A reduction in muscle size (muscle wasting) due to inactivity or immobilization.
Autogenic inhibition
An automatic reflex relaxation caused by stimulation of the Golgi tendon organ (GTO).
Autonomic nervous system
The part of the nervous system that regulates involuntary body functions, including the activity of the cardiac muscle, smooth muscles, and glands. It has two division: the sympathetic nervous system and the parasympathetic nervous system.
Autoregulation
Local control of blood distribution (through vasodilation) in response to a tissue’s changing metabolic needs.
Axial skeleton
The bones of the head, neck, and trunk.
Axis of rotation
The imaginary line or point about which an object, such as a joint, rotates.
Axon
A nerve fiber that conducts a nerve impulse away from the neuron cell body; efferent nerve fiber.
Balance
The ability to maintain the body’s position over its base of support within stability limits, both statically and dynamically.
Ballistic stretching
Dynamic stretching characterized by rhythmic bobbing or bouncing motions representing relatively high-force, short-duration movements.
Base of support (BOS)
The areas of contact between the feet and their supporting surface and the area between the feet.
Beta cells
Endocrine cells in the islets of Langerhans of the pancreas responsible for synthesizing and secreting the hormone insulin, which lowers the glucose levels in the blood.
Beta oxidation
Metabolic pathway involving the breakdown of fatty acids (digested dietary fat) for the production of ATP.
Bile
A greenish-yellow or brownish emulsifier that prepares fats and oils for digestion; produced in and secreted by the liver, stored in the gallbladder, and released into the small intestine.
Binge eating disorder (BED)
An eating disorder characterized by frequent binge eating (without purging) and feelings of being out of control when eating.
Bioavailability
The degree to which a substance can be absorbed and efficiently utilized by the body.
Biomechanics
The mechanics of biological and muscular activity.
Body composition
The makeup of the body in terms of the relative percentage of fat-free mass and body fat.
Body mass index (BMI)
A relative measure of body height to body weight used to determine level of weight, from underweight to extreme obesity.
Bolus
A food and salvia digestive mix that is swallowed and then moved through the digestive tract.
Bone mineral density (BMD)
A measure of the amount of minerals (mainly calcium) contained in a certain volume of bone.
Bronchi
The two large branches of the trachea leading into the lungs.
Bronchioles
The smallest tube that supply air to the alveoli (air sacs) of the lungs.
Brush border
The site of nutrient absorption in the small intestines.
Bulimia nervosa (BN)
An eating disorder characterized by recurrent episodes of uncontrolled binge eating; recurrent inappropriate compensatory behavior such as self-induced vomiting, laxative misuse, diuretics, or enemas (purging type), or fasting and/ or excessive exercise (non-purging type); episodes of binge eating and compensatory behaviors occur at least twice per week for three months; self-evaluation is heavily influenced by body shape and weight; and the episodes do not occur exclusively with episodes of anorexia.
Bulk element
An element (such as certain minerals) that animals require in large amounts.
Calorie
A measurement of the amount of energy in a food available after digestion. The amount of energy needed to increase 1 kilogram of water by 1 degree Celsius. Also called a kilocalorie.
Capillaries
The smallest blood vessels that supply blood to the tissues, and the site of all gas and nutrient exchange in the cardiovascular system. They connect the arterial and venous systems.
Carbohydrate
The body’s preferred energy source. Dietary sources include sugars (simple) and grains, rice, potatoes, and beans (complex). Carbohydrate is stored as glycogen in the muscles and liver and is transported in the blood as glucose.
Carbohydrate loading
Up to a week-long regimen of manipulating intensity of training and carbohydrates intake to achieve maximum glycogen storage for an endurance event.
Cardiac accelerator nerves
Part of the sympathetic nervous system that stimulates the SA node to increase heart rate.
Cardiac cycle
The period from the beginning of one heartbeat to the beginning of the next heartbeat; the systolic and diastolic phase and the interval in between.
Cardiac output
The amount of blood pumped by the heart per minute; usually expressed in liters of blood per minute.
Cardiac sphincter
Site at the upper portion of the stomach; prevents food and stomach acid from splashing back into the esophagus from the stomach; also called the esophageal sphincter.