abduction
To draw away from or deviate from the midline of the body;
opposite of adduction; side movement away from the midline of the body; Example,
a side leg raise moving the leg away from the body’s center.
abrasion
A scraping away of skin or mucous membrane as the result of
an injury or by other mechanical means.
abs
Slang for rectus abdominus muscle.
Acceptable daily intake (ADI)
The amount of chemical that, if ingested
daily over a lifetime, appears to be without appreciable effect.
acclimatization
The process of becoming accustomed (physiologically
adapting) to an unfamiliar environment, for example, the body can adjust
to a high altitude or a hot climate and increase its capacity to work in
those conditions.
accommodative resistance
The application of a resistive force that controls
the speed with which an individual is able to move, thereby allowing him
to work at maximal resistance throughout the complete range of motion; this
is very useful during rehabilitation, when injuries are present, and also
in sports training for speed-strength; also referred to as isokinetic resistance;
see also isokinetic resistance.
acesulfame K
Acesulfame K, or acesulfame potassium, is a low-calorie
sweetener approved for use in the United States in 1988. It is an organic
salt consisting of carbon, nitrogen, oxygen, hydrogen, sulphur and potassium
atoms. It is 200 times sweeter than sucrose, has a synergistic sweetening
effect with other sweeteners, has a stable shelf-life and is heat stable.
It is excreted through the human digestive system unchanged, and is therefore
non-caloric.
acetyl Co-A
Acetyl Co-enzyme A; a substance that is formed by an acetyl
group attaching itself to coenzyme A (CoA); the acetyl group is formed either
from pyruvate, the breakdown product of glycolysis (the breakdown of sugars),
or beta-oxidation (the breakdown of fats), and is used to enter the Kreb’s
cycle and generate energy in the form of ATP.
Achilles tendinitis
Inflammation of the Achilles tendon (tendon found
at the back of the heel); rest and ice are the two recommended treatments
for Achilles tendinitis.
acid-base balance
The mechanisms by which the pH of the body fluids
are kept in a state of balance so that arterial blood is kept at a constant
pH level of 7.35 to 7.45; The pH of blood is kept from becoming too acidic
or alkaline through respiration, buffers, and work done by the kidney.
acromegaly
A chronic disorder developing in adult life characterized
by increased massiveness of the bones, organs and other body parts and elongation
and enlargement of the bones of the extremities and certain head bones,
especially of the frontal bone and jaws, with enlargement of the nose and
lips and thickening of the soft tissues of the face; caused by increased
levels of growth hormone.
actin
One of the fibrous contractile proteins found in a myofibril.
active (dynamic) stretching
A technique in stretching muscle and tissue
that requires muscle contraction through a range of motion; no outside force
is involved.
active recovery
Performing light aerobic exercise, stretching exercises,
or working other body parts to facilitate recovery after intense exercise
to allow for more productive use of exercise time and to encourage blood
flow to the muscles.
actomyosin
The protein complex involved in muscle contraction and relaxation
which is composed of actin and myosin protein filaments.
acute
Having a rapid onset; sharp, severe; opposite of chronic.
adaptation
The ability of the body to adjust; Example, the body’s
ability to adjust to hot or cold climates.
additives
Substances other than a foodstuff present in food as a result
of production, processing, storage or packaging; Examples, preservatives,
coloring, thickeners (gums), and binders.
additives (food additives)
Any natural or synthetic material, other
than the basic raw ingredients, used in the production of a food item to
enhance the final product. Any substance that may affect the characteristics
of any food, including those used in the production, processing, treatment,
packaging, transportation or storage of food.
adduction
To bring toward the midline of the body; opposite of abduction;
Example, bringing the elbows together in front of the body like a chest press
working the pectoralis muscle.
adenosine triphosphate (ATP)
A high-energy molecule from which the body
derives its energy; produced aerobically and anaerobically, and stored in
the body.
Adequate Intake (AI)
A value established through experimental or
observational data that show a mean intake which appears to sustain a desired
indicator or health when sufficient scientific evidence is not available
to estimate an average requirement and no RDA exists. The AIs are part of
the DRIs.
adherence
The degree to which an individual follows a given prescribed
program; for example, the amount of activity engaged in during a specified
time period compared to the amount of activity recommended for that time
period.
adipose tissue
Fatty tissue; connective tissue made up of fat cells.
ADP
Adenosine di-phosphate, a high energy phosphate molecule involved
in the production and storage of energy. The end product of the mono-phosphate
reduction of ATP.
aerobic
With, or in the presence of, oxygen; Aerobic metabolism most
efficiently produces the basic energy source, adenosine triphosphate (ATP).
Walking, jogging, biking, an aerobic exercise class and any activity which
maintains the heart rate in the THR zone for a minimum of 20 minutes is aerobic
activity. Tennis and basketball are not considered aerobic activities.
aerobic exercise
Aerobic exercise refers sustained exercise that uses
large muscle groups and places demands on the cardiovascular system.
aerobic exercise (training)
Exercise with the purpose of developing
aerobic or cardiovascular conditioning; activities in which oxygen from the
blood is required to fuel the energy-producing mechanisms of muscle fibers;
Examples, running, cycling, rowing, cross-country skiing.
aerobic interval training
Training method characterized by intervals
of high and low intensity of pre-determined duration; heart rate typically
remains at 60-80% of MHR, with 2-15 minute intervals; used to develop the
aerobic energy system.
aerobic threshold intervals
Used to develop ability to use oxygen while
performing at a higher intensity; exercise is performed for a pre-determined
time at anaerobic threshold, combined with a period of active recovery; This
training can be modified in terms of intensity and duration of the exercise
interval and the number of work intervals per workout.
afterburn
Calories used due to an increase in metabolic rate following
exercise activities.
agonist (muscle)
Muscle that is directly involved in contraction; primarily
responsible for movement; opposes the action of an antagonist (opposite)
muscle. During a bicep curl, the bicep is the active muscle or agonist; compare
antagonist.
allergen (food allergen)
A food allergen is the part of a food (a protein)
that stimulates the immune system of food allergic individuals. A single
food can contain multiple food allergens. Carbohydrates or fats are not
allergens.
allergy (food allergy)
A food allergy is any adverse reaction to an
otherwise harmless food or food component (a protein) that involves the body's
immune system. To avoid confusion with other types of adverse reactions to
foods, it is important to use the terms "food allergy" or "food hypersensitivity"
only when the immune system is involved in causing the reaction.
all-or-none principle
The principle of muscle contraction that states
that when a motor unit is activated, all of the muscle fibers in that given
motor unit will maximally contract or not contract at all.
amenorrhea
The absence of menstruation; somewhat more common in women
engaging in excessive exercise; thorough medical exam is required to determine
the exact cause.
amino acids
Amino acids function as the building blocks of proteins.
Chemically, amino acids are organic compounds containing an amino (NH2) group
and a carboxyl (COOH) group. Amino acids are classified as essential,
nonessential and conditionally essential. If body synthesis is inadequate
to meet metabolic need, an amino acid is classified as essential and must
be supplied as part of the diet. Essential amino acids include leucine,
isoleucine, valine, tryptophan, phenylalanine, methionine, threonine, lysine,
histidine and possibly arginine (conditionally essential). Nonessential amino
acids can be synthesized by the body in adequate amounts, and include alanine,
aspartic acid, asparagine, glutamic acid, glutamine, glycine, proline and
serine. Conditionally essential amino acids become essential under certain
clinical conditions.
AMP
Adenosine mono-phosphate, a phosphate molecule involved in the
production of energy in the body. The end product of the mono-phosphate reduction
of ADP or the di-phosphate reduction of ATP. Used to regenerate ATP levels.
anabolic androgenic steroids
A general class of hormones (or synthetic
derivatives) of the male sex hormone testosterone which simulates
testosterone’s tissue building and masculinizing properties.
anabolism
The metabolic processes which build up body tissue; Example,
muscle-building; anabolism is the opposite of catabolism.
anaerobic
Outside the presence of oxygen; not requiring oxygen; Anaerobic
activities produce higher levels of lactic acids and carbon dioxide than
aerobic activities. Short duration activities, requiring bursts of energy,
are usually anaerobic.
anaerobic exercise
Short-term, highly intense activities in which muscle
fibers derive energy for contraction from stored internal energy sources
without the use of oxygen from the blood; stored energy sources include ATP,
CP, and glycogen; Examples, short burst, intense efforts, such as in sprinting
or weightlifting.
anaerobic glycolysis
The metabolic pathway that uses glucose or stored
glycogen 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 interval training
Training designed to teach the body to derive
energy from the anaerobic system to improve muscular strength and speed and
develop the athlete’s ability to remove lactate from the muscles;
characterized by intervals of higher and lower intensity; Aerobic interval
training typically exceeds 85% of MHR with 30 second to 4 minute intervals.
anaerobic threshold
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 planes
Three planes of the human body in the anatomical position:
sagittal, frontal, and transverse.
anatomical position
Description of human body when body is erect, arms
are down at sides, and palms are forward; used for describing positions on
the body or directions of movement of the body.
anatomy
The study of the structure of an organism or its elements; Human
anatomy refers to the study of the human body.
anemia
Anemia is a condition in which a deficiency in the size or number
of erythrocytes (red blood cells) or the amount of hemoglobin they contain
limits the exchange of oxygen and carbon dioxide between the blood and the
tissue cells. Most anemias are caused by a lack of nutrients required for
normal erythrocyte synthesis, principally iron, vitamin B-12, and folic acid.
Others result from a variety of conditions, such as hemorrhage, genetic
abnormalities, chronic disease states or drug toxicity.
anemic
Condition characterized by a reduction below normal of the number
of red blood cells or hemoglobin in the blood, often displaying symptoms
of fatigue.
angina
See angina pectoris.
angina pectoris
Pain in the chest due to insufficient blood supply and
oxygen to the heart; can be characterized as a crushing pain or by a substantial
"pressure" sensation within the chest, commonly radiating down the arm, up
into the jaw, or to another site; Angina pectoris is caused by an obstructed
coronary artery and insufficient oxygen to the heart muscle.
Anorexia Nervosa
An eating disorder characterized by refusal to maintain
a minimally normal weight for height and age. The condition includes weight
loss leading to maintenance of body weight 15 percent below normal; an intense
fear of weight gain or becoming fat, despite the individual's underweight
status; a disturbance in the self-awareness of one's own body weight or shape;
and in females, the absence of at least three consecutive menstrual cycles
that would otherwise be expected to occur.
Anorexia Nervosa
A psychological eating disorder characterized by refusal
to maintain a minimally normal weight for height and age; This condition
includes: weight loss leading to maintenance of body weight 15 percent below
normal; an intense fear of weight gain or becoming fat despite the individual's
underweight status; a disturbance in the self-awareness of one's own body
weight or shape; and in females, the absence of at least three consecutive
menstrual cycles that would otherwise be expected to occur. Metabolic
abnormalities are commonly associated with this disorder and can sometimes
be fatal.
antagonist
Muscle that works against or in opposition of an agonist
muscle; while one muscle group flexes, another extends; During a biceps curl,
the biceps is the agonist and the triceps is the antagonist; see also agonist.
anterior
Toward the front; frontal segment; Example: the quadriceps
are anterior to the hamstring.
anthropometric measurements
Measurement and analysis of parts of the
human body; Examples, skinfold, girth, and body weight.
antibiotics
Antibiotics are used in animal agriculture for two reasons.
First, to improve the rate of growth and the feed efficiency of animals so
they produce more meat or milk on less feed. The second reason is to prevent
and treat diseases, just as in humans.
antibody
Protein produced by the immune system of humans and higher
animals in response to the presence of a specific antigen.
antigen
A foreign substance (almost always a protein) that, when introduced
into the body, stimulates an immune response.
antioxidant
Antioxidants protect key cell components by neutralizing
the damaging effects of "free radicals," natural byproducts of cell metabolism.
Free radicals form when oxygen is metabolized, or burned by the body. They
travel through cells, disrupting the structure of other molecules, causing
cellular damage. Such cell damage is believed to contribute to aging and
various health problems. Antioxidants include vitamins A, C, E, and selenium.
Other potential antioxidants include pycnogenol, nordihydroguairetic acid
(NDGA), glutathione, superoxide dismutase, and others. Antioxidants are also
referred to as free-radical "scavengers".
antisense
A piece of DNA that produces the mirror image, or antisense
messenger RNA, that is exactly opposite in sequence to one that directs the
cells to produce a specific protein. Since the antisense RNA binds tightly
to its image, it prevents the protein from being made.
aorta
The main arterial vessel; arises from the left ventricle of the
heart and carries blood to all parts of the body; The aorta is the largest
artery in the body.
aponeurosis
A broad, flat tendinous sheet of connective tissue that
extends from the fibrous wrapping of a muscle and connects that muscle to
adjacent structures, usually the wrappings of another muscle.
arachidonic acid
An omega-6 essential fatty acid which is an important
precursor to the formation of prostaglandins.
arrhythmia
Abnormal heart rhythm or beat.
arteries
Vessels that carry oxygenated blood away from the heart; the
carotid artery is commonly used to monitor the heart rate.
arterioles
Smaller divisions of the arteries as they get farther away
from the heart and lead to capillaries.
arteriosclerosis
The hardening, thickening or loss of elasticity of
the wall of an artery; precedes cardiovascular disease such as stroke and
coronary artery disease; Arteriosclerosis is sometimes referred to as "hardening
of the arteries".
arthritis
Inflammation of one or more joints; a potentially painful
disorder that limits comfortable range of motion; The exercise prescription
for arthritis should include slow, controlled exercises that work the full
range of motion; see also osteoarthritis and rheumatoid arthritis.
articulation
Place of union or junction between two or more bones; joint.
aspartame
Aspartame is a low-calorie sweetener used in a variety of
foods and beverages and as a tabletop sweetener. It is about 200 times sweeter
than sugar. Aspartame is made by joining two amino acids, aspartic acid and
phenylalanine.
asthma
Asthma is a chronic medical condition, affecting approximately
10 million Americans (3 to 4 percent of the population). Asthma results when
irritants (or trigger substances) cause swelling of the tissues in the air
passage of the lungs, making it difficult to breathe. Typical symptoms of
asthma include wheezing, shortness of breath and coughing.
asthma
An intermittent obstruction of the tubes that carry air to and
from the lungs characterized by episodes of difficulty breathing; For some,
asthma is brought on only by exercise. Symptoms of exercise-induced asthma
are coughing and shortness of breath after only 8-12 minutes of exercise.
Participants should consult a doctor and obtain an exercise prescription.
atherosclerosis
A condition that exists when too much cholesterol builds
up in the blood and accumulates in the walls of the blood vessels, often
referred to as ‘hardening of the arteries’.
atherosclerosis
The most common and serious form of arteriosclerosis;
Fatty substances and other debris collect in the inner lining of the arteries,
forming plaques that encroach upon the passageway and gradually obstruct
the flow of blood. Atherosclerosis is associated with a high-fat diet.
athlete’s heart
An enlarged heart muscle found in endurance athletes;
Athlete’s heart is the result of large, strong muscle fibers in the
heart’s left ventricle, which are well conditioned by pushing out a
great volume of blood.
atom
The smallest divisible unit of an element in nature in which that
element still holds its natural properties as that element.
ATPase
Enzyme which acts to split the ATP molecule.
ATP
Adenosine triphosphate, a high energy phosphate molecule used to
store and release energy for work within the body.
ATP
Adenosine triphosphate, a high-energy molecule from which the body
derives its energy; see also adenosine triphosphate.
ATP-CP system
Energy system that utilizes ATP and creatine phosphate;
see also adenosine triphosphate and creatine phosphate.
atrium
One of the two (left and right) upper chambers of the heart (Pl.
atria); acts as a collection chamber for the heart prior to entering the
ventricles to leave the heart .
atrophy
Decrease in the cross-sectional size of a muscle due to lack
of use or disease; Example: the arm, after it has been in a cast for a period
of time, is usually smaller than before it was broken.
Attention Deficit Hyperactivity Disorder (ADHD)
Commonly called
"hyperactivity," Attention Deficit Hyperactivity Disorder is a clinical diagnosis
based on specific criteria. These include excessive motor activity,
impulsiveness, short attention span, low tolerance to frustration and onset
before 7 years of age.
autogenic inhibition
Automatic relaxation reflex caused by excessive
stimulation of Golgi tendon organs (GTOs).
avascular
Lacking in blood vessels or having a poor blood supply; not
vascular; said of tissues such as cartilage and ligaments.
avulsion
The forcible separation or tearing of tissue from the body.
axis of rotation
The imaginary line or point about which an object,
such as a body or a lever, rotates.
