ISSA Personal Fitness Training Exam Study Guide with Complete Solutions

cuboidal epithelium: Epithelial tissue consisting of one or more cell layers, the most superficial of which is composed of cube-shaped or somewhat prismatic cells. rep out: Repeat the same exercise movement until you are unable to continue. watt: A measure of power (work performed per unit of time) involving a known force, distance and time frame. Equal to 6.12 kilogram-meters per minute. zoonutrients Food molecules that have been shown to have potential in modifying multiple physiological functions including anti-inflammatory, antihypertension, antimicrobial actions, stimulation of beneficial bacteria, the maturation of intestinal cells, and the education of the immune system. zoochemicals Nutrients that are only found in animal products which contain nutrients such as EPA and DHA (the fish oils), CLA (another fatty acid), creatine, and carnosine. zinc Has significant roles in protein synthesis, maintenance of enzyme systems, contractibility of muscles, formation of insulin, synthesis of DNA, healing processes, prostrate health, and male reproductive fluid. RDA: 15 mg. Deficiencies are common due to food processing and zinc-poor soil. Excessive sweating can drain up to 3 mg. daily. Dietary sources: meat, wheat germ, brewer's yeast, pumpkin seeds, eggs. Zinc chelate is the element zinc in supplemental form and coated with protein, thus increasing the percentage that can be assimilated by the body. Deficiency in zinc is associated with anemia, short stature, hypogonadism, impaired wound healing, and geophagia. Zinc salts are often poisonous when absorbed by the system, producing a chronic poisoning resembling that caused by lead. Z lines Any of the dark bands across a striated muscle fiber that mark the junction of actin filaments in adjacent sarcomeres. workrate Power. The amount of work done per unit of time. Can be measured in foot-pounds per second, watts, horsepower, etc. workout A complete exercise session, ideally consisting of warm-up, intense aerobic, and/or strength exercises, and cool-down. work Force times distance. Measured in foot-pounds and similar units. Example: Lifting a 200-pound barbell 8 feet and lifting a 400-pound barbell 4 feet each require 1,600 foot-pounds of work. whole foods Food that has been processed or refined as little as possible and is free from additives or other artificial substances. white blood cell Nucleated cells, originating from the bone marrow, that make up the infection-fighting components of the blood. White blood cells fight infections by producing antibodies, releasing immune factors, or ingesting invading bacteria or viruses. wellness A state of health more positive than the mere absence of disease. Wellness programs emphasize self-responsibility for a lifestyle process that realizes the individual's highest physical, mental, and spiritual well-being. weightlifting An Olympic sport where athletes compete in defined weight classes to lift the most weight overhead. The two lifts contested are the snatch and the clean and jerk. Three attempts are given in each of the two lifts. See also Olympic lifts. weightlifter’s headache An exertional type of pain which may be due to intense clenching of the jaws during heavy lifts. weight training belt Thick leather belt developed by weightlifters in the early part of the century, usually four inches wide in the back and two inches wide in the front, used to support lower back while doing squats, military presses, dead lifts, bent rowing, etc. A more comfortable narrow belt going around the back, is far superior to the belts traditionally worn. This new belt is called a "LORA" (acronym for Lumbar Orthopedic Repositioning Appliance). weight training: Physical training that involves lifting weights. warm-up: A gradual increase in the intensity of exercise to allow physiological processes to prepare for greater energy outputs. Changes include rise in body temperature, cardiovascular- and respiratory-system changes, increase in muscle elasticity and contractility, etc. Flexibility exercises and stretching are NEVER advised as a warm-up strategy because of the damage that is easily caused to cold muscles. waist-to-hip ratio Your waist girth divided by your hip girth. People who carry excess fat in their abdominal area (the "apple" shape) appear to be at greater risk for diabetes, heart disease and high blood pressure than those who carry weight in the hips and thighs (the "pear" shape). For women, a desirable waist -to-hip ratios is 0.8 or lower. For men, the number is 1.0 or lower. waist circumference Refers to a numerical measurement of your waist. voluntary muscle tissues Receive nerve fibers from the somatic nervous system that can be voluntarily controlled (e.g., skeletal muscles). VO2 max Maximum Volume of Oxygen consumed per unit of time. In scientific notation, a dot appears over the V to indicate "per unit of time." See also maximal oxygen uptake. vitamin K (“Koagulation”) This vitamin is implicated in proper blood clotting. It is synthesized in the intestinal flora. Because it is fat-soluble, it has the potential for toxicity if taken in large doses. There is no established RDA. vitamin E This fat-soluble vitamin is an active antioxidant retarding free-radical damage, as well as protecting oxidation of fat compounds, vitamin A, and other nutritional factors in the body. Important to cellular respiration, proper circulation, protection of lungs against air pollution, and prevention of blood clots. Helps alleviate leg cramps and "charley horse." RDA: 15 International units (men), 12 (women). Dietary sources: wheat germ, cold-pressed vitamin D A fat-soluble vitamin, acquired through sunlight or diet. Aids the body in utilization of vitamin A, calcium, and phosphorus. Helps maintain stable nervous system and normal heart action. RDA: 400 International units. Dietary sources: fish-liver oils, sardines, salmon, tuna, milk and dairy. vitamin C A critical health-protection nutrient. Body stores are depleted rapidly by drugs, toxins, smoking, exercise, and stress. Fortifies the immune system against virus infections, strengthens blood vessels, reduces cardiovascular abnormalities, lowers fat, and cholesterol levels; as a natural anesthetic, it reduces many kinds of pain, helps detoxify chemical and metal contaminants found in the air, water, and food, slows down lactic acid buildup, helps heal wounds, scar tissue, and injuries. Necessary in the formation of connective tissue. RDA: 60 mg, but tolerated in doses exceeding 10,000 mg (10 grams) daily. Dietary sources: citrus fruits, berries, green and leafy vegetables, tomatoes, potatoes. vitamin B-Complex A family of 13 water-soluble vitamins, probably the single-most important factor for the health of the nervous system. They are essential to the conversion of food into energy. When you exercise strenuously, your body quickly burns up its vitamin B supply. A shortage of Bs affects both performance and recovery. High consumption of sugar, caffeine, processed food and alcohol cause depletion. These vitamins are grouped together because of their common source, distribution, and their interrelationship as coenzymes in metabolic processes. All must be present together for the B-complex to work. vitamin B-complex consists of the following vitamins: biotin, choline, inositol, vitamin B-1 (thiamine), vitamin B-2 (riboflavin), vitamin B-3 (niacin), vitamin B-5 (pantothenic acid), vitamin B-6 (pyridoxine), vitamin B-9 (folacin), vitamin B-12 (cyanocobalamin). The best food source for vitamin B-complex is Brewer's yeast. vitamin B-6 (pyridoxine) Essential for the production of antibodies and red blood cells, and the proper assimilation of protein. The more protein you eat, the more B-6 you need! Facilitates conversion of stored liver and muscle glycogen into energy. RDA: 1.8 mg. (men), 1.5 mg. (women). Dietary sources: brewer's yeast, wheat bran, wheat germ, liver, kidney, cantaloupe. vitamin B-5 (pantothenic acid) An important stress, immune system and anti-allergy factor. Vital for proper functioning of adrenal glands, where stress chemicals are produced. Promotes endurance. RDA: 10 mg. Dietary sources: organ meats, egg yolks, whole-grain cereals. vitamin B-3 (niacin) Essential for synthesis of sex hormones, insulin, and other hormones. Effective in improving circulation and reducing blood cholesterol. RDA: 19 mg. (men), 13 mg. (women). Dietary sources: lean meats, poultry, fish and peanuts. vitamin B-2 (riboflavin) An essential cofactor in the enzymatic breakdown of all foodstuffs. Important to cell respiration, good vision, skin and hair. RDA: 1.6 mg. Dietary sources: liver, tongue, organ meats, milk, eggs. The amount found in foods is minimum, making this America's most common vitamin deficiency. vitamin B-12 (cobalamin) Necessary for normal metabolism of nerve tissue and formation and regeneration of red blood cells. RDA: 3 micrograms. Dietary sources: animal protein. Liver is the best. vitamin B-1 (thiamine) Essential for learning capacity and muscle tone in the stomach, intestines and heart. RDA: 1.4 mg (men), 1.0 mg. (women). Dietary sources: brewer's yeast, wheat germ, blackstrap molasses, whole wheat and rice, oatmeal, most vegetables. vitamin A A fat-soluble vitamin occurring as preformed vitamin A (retinol), found in animal origin foods, and provitamin A (carotene), provided by both plant and animal foods. Maintains healthy skin, mucous membranes, eyesight, immune system function, and promotes strong bones and teeth. Vital to the liver's processing of protein. RDA: 5,000 International units. Dietary sources: fish liver oil, liver, eggs, milk and dairy, green and yellow vegetables, and yellow fruits. vitamin: Organic food substances present in plants and animals, essential in small quantities for the proper functioning of every organ of the body, and for all energy production. They must be obtained through diet because they cannot be synthesized by the body vital signs: The measurable signs of essential bodily functions, such as respiration rate, heart rate, temperature, blood pressure, etc. vital capacity: Maximal breathing capacity; the amount of air that can be expired after a maximum inspiration; the maximum total volume of the lungs, less the residual volume. The usable portion of the lungs. visual reference point: A chosen point of focus to aid in stability and balance. visual domain: The learning style or process that results in new knowledge (or understanding) with the involvement of visiual input. This can be accomplished through the use of visual aids, demonstrations, or visual cues. vertigo: Sensation that the world is spinning or that the individual is revolving; a particular kind of dizziness. vertebral joint fixation: A neurosurgical procedure in which two or more vertebrae are anchored to each other through a synthetic “vertebral fixation device”, with the aim of reducing vertebral mobility and thus avoiding possible damage to the spinal cord and/or spinal roots. ventilation: Breathing. See also expiration, inspiration, respiration. velocity: The speed of something in a given direction. vein: A vessel which returns blood from the various parts of the body back to the heart. vasodilation: The enlarging of a blood vessel to increase blood flow to a body part. vasoconstriction: The narrowing of a blood vessel to decrease blood flow to a body part. vascularity: Increase in size and number of observable veins. Highly desirable in bodybuilding. variable split training: A weight training system developed in the mid 80s by Dr. Fred Hatfield that systematizes workout schedules according to the recuperation of individual muscle groups and body parts. This method maximizes development by eliminating effects of overtraining or undertraining. Also variable double split and variable triple split for multiple daily workouts. variable resistance: Strength training equipment which can, through the use of elliptical cams and other such technology, vary the amount of weight being lifted to match the strength curve for a particular exercise. Nautilus machines, for example, provide this feature. See also constant resistance and accommodating resistance. valvular heart disease: Any disease process involving one or more of the four valves of the heart (the aortic and mitral valves on the left and the pulmonary and tricuspid valves on the right). Valsalva maneuver: If the glottis (the narrowest part of the larynx) is closed following full inspiration and the expiratory muscles are fully activated, the compressive forces of exhalation can increase the intrathoracic pressure from 2 or 3 mm Hg to upwards of 100 mm Hg above atmospheric pressure. This forced exhalation against a closed glottis is called the Valsalva maneuver (named after the Italian anatomist who first explained the phenomenon), and is common in weightlifting or other activities requiring short rapid maximum force application. The intrathoracic pressure causes the veins to compress and this in turn results in significantly reduced venous blood flow into the heart and into the brain. Dizziness, “spots” before the eyes, and blackout can ensue. This is one good reason why those with cardiac problems should refrain from all-out straining (as in isometric contraction) and instead should engage in a more rhythmic type of weightlifting technique. urinary system: Main excretory system of the body, which consists of the kidneys, ureter, urinary bladder, and urethra. upper abs: Abdominal muscles above navel. See also lower abs. unstable surface training: A training method in which unstable surfaces are used to enhance general balance and contraction potential throughout the body. unsaturated fatty acids (UFA): Important in lowering blood cholesterol and may thus help prevent heart disease. They are essential for normal glandular activity, healthy skin, mucous membranes, and many metabolic processes. Unsaturated fatty acids (UFA) are fatty acids whose carbon chain contains one or more double or triple bonds, and which are capable of receiving more hydrogen atoms. They include the group polyunsaturates, are generally liquid at room temperature, and are derived from vegetables, nuts, seeds, or other sources. Examples of unsaturated fatty acids include corn oil, safflower oil, sunflower oil, and olive oil. Replacing saturated fats with unsaturated fats in the diet can help reduce cholesterol levels. A small amount of highly unsaturated fatty acid is essential to animal nutrition. The body cannot desaturate a fat, such as vegetable shortening or margarine, sufficiently by its own metabolic processes to supply this essential need. Therefore, the dietary inclusion of unsaturated or polyunsaturated fats is vital. The three essential fatty acids (those which the body is unable to manufacture) are linoleic acid, linolenic acid, and arachidonic acid. However, these fatty acids can be synthesized from linoleic acid if sufficient intake occurs. Linoleic acid should provide about 2% of total dietary calories. Corn, safflower, and soybean oils are high in linoleic acid. See also monounsaturated fat, polyunsaturated fat, saturated fat. ultrasound: Sound or other vibrations having an ultrasonic frequency, particularly as used in medical imaging. ulcers: An open sore on an external or internal surface of the body, caused by a break in the skin or mucous membrane that fails to heal. type IIx: A fast-twitch fiber subdivision characterized by the most rapid shortening velocity and greatest anaerobic potential. type IIc: A fast-twitch fiber that results from the “fusion” of type IIx with surrounding satellite cells. type IIa: A fast-twitch fiber subdivision characterized by a fast shortening speed and welldeveloped capacity for energy transfer from aerobic and anaerobic sources. type II muscle fibers (fast twitch): Muscle fiber type that contracts quickly and is used mostly in intensive, short-duration exercises. Type II diabetes (non-insulin dependent): A chronic condition that affects the way your body metabolizes sugar (glucose), your body’s important source of fuel. type I muscle fibers (slow twitch): A muscle fiber characterized by its slow speed of contraction and a high capacity for aerobic glycolysis. Generates ATP predominantly through the aerobic system of energy transfer. Type I diabetes (insulin-dependent): A chronic condition in which the pancreas produces little or no insulin, a hormone needed to allow sugar (glucose) to enter cells to produce energy. two-joint-muscles: Muscles that cross two joints rather than just one, such as the hamstrings which cross both the hip and the knee. twitch: A brief muscle contraction caused by a single volley of motor neuron impulses. See also fast-twitch fibers, slow-twitch fibers. true synergy: When a muscle contracts to stop the secondary action of another muscle. triglycerides: The storage form of fat made up of three fatty acids and a glycerol group. triceps brachii: The muscles on the back of the upper arm, prime movers for extending the elbow. traps: Slang for trapezius muscles, the largest muscles of the back and neck that elevates the shoulder girdle and draws the scapulae medially. transverse (horizontal) plane: Separates the body into superior (top) and inferior (bottom) sections. transport proteins: A protein that serves the function of moving other materials within an organism. training to failure: Continuing a set in weight training until inability to complete another rep without assistance. training zone: Defined zones, typically based on heart rate, that determine at what level of intensity an individual should be training. training technologies: Athletes can tap into eight broad categories of accepted methods to attain performance goals: weight training, light resistance training, medical support, therapeutic modalities (Jacuzzi, massage, acupuncture, etc), psychological support, biomechanics, diet and nutritional supplements. training effect: An increase in functional capacity of muscles and other bodily tissues as a result of increased stress (overload) placed upon them. training: Subjecting the body to repeated stresses with interspersed recovery periods to elicit growth in its capacity to handle such stresses. total daily energy expendature (metabolic rate): A summation of all things your body does both actively and passively to burn calories in 24 hour period. total body fat: Total amount of body fat throughout the body in the way of either body fat percentage, or weight in body fat. torque: The magnitude of twist around an axis of rotation (fulcrum). Tmax: Aspect of the strength curve. Measurement of how long it takes from the beginning of upwards (concentric) movement to exert maximum force (Fmax). tissue elasticity: Also known as viscoelasticity: involved in all explosive sports, including shot put, boxing, the baseball and javelin throw, and powerlifting. After being stretched, most bodily tissues: including muscles, but not so much with ligaments and tendons: return to their original shape or length. The quicker they do, the more force there is added to the force output stemming from both stretch reflex and muscle contraction. tissue: A collection of similar cells and their intracellular substances. tissue (or interstitial) Leverage: The degree of extra mechanical advantage gained by super heavyweight strength athletes by packing sheer mass from extra fat, liquid and protein between and inside muscle fibers. thyrotoxicosis: Also known as hyperthyroidism. A condition resulting from excessive concentrations of thyroid hormones in the body. thrombosis: Local coagulation or clotting of the blood in a part of the circulatory system. thixotropy: A time-dependent shear thinning property. Certain gels or fluids that are thick (viscous) under static conditions will flow (become thin, less viscous) over time when shaken, agitated, or otherwise stressed (time dependent viscosity). third-class lever: A lever in which the effort is placed between the fulcrum and the load. thermic effect of feeding (TEF): How metabolism responds to the digestion of food and the uptake of nutrients in the blood. thermic effect: The heat liberated from a particular food; it is a measure of its energy content and its tendency to be burned as heat. This process of heat liberation is also commonly referred to as “thermogenesis.” therapy: Treatment of illness or disability. testosterone: The sex hormone that predominates in the male is responsible for the development of male secondary sex characteristics and is involved in the hypertrophy of muscle. See also estrogen. Anabolic steroids are synthetic chemicals that mimic the muscle-building effects of testosterone. Testosterone is an androgen, a sex hormone produced by all humans. It is important in the development of male gonads and sex characteristics. In females, testosterone is an intermediate product in the production of estradiols. As a pharmaceutical drug, it is used to stimulate sex characteristics, to stimulate production of red blood cells, and to suppress estrogen production. Long-term use can lead to kidney stones, unnatural hair growth, voice changes, and decreased sperm count. tendonitis: Inflammation of a tendon. tendon: A band or cord of strong, fibrous (collagenous) connective tissue that connects muscles to bone. target heart rate (THR): A specific age-based pulse rate to be maintained during aerobic exercise to ensure optimal cardiovascular function. Aiming for THR of 60 to 90 percent of maximum heart rate reserve. tachycardia: Excessively rapid heart rate. Usually describes a pulse of more than 100 beats per minute at rest. See also bradycardia. systolic pressure: Aspect of a blood pressure reading which indicates the maximum arterial pressure occurring during contraction of the left ventricle of the heart. systole: The contraction, or time of contraction, of the heart. See also diastole. synovial fluid: A fluid that lubricates the smooth cartilage in joints. synergism: The combined effect of two or more parts of forces or agents which is greater than the sum of the individual effects. Example: the synergistic effect of a multiple vitamin and mineral formula compared to the benefits of one or two vitamins. syndrome: A group of related symptoms or signs of disease. symptom-limited maximal GXT: An exercise test wherein the exercise intensity will continuously increase. Once the cardiovascular system starts showing signs of reaching its limit, the test ends and analyzing the information gathered begins to determine how hard the heart was working. symptom: Any evidence by which a person perceives that he/she may not be well; subjective evidence of illness. See also sign. sympathetic overtraining: A category of overtraining in which the sympathetic part of the nervous system becomes overactive which results in the classic sign of an increased resting heart rate. sympathetic nervous system: An automatic system that speeds up most activities in the body. sustainable: Ability to be maintained at a certain rate or level. supplements: Any interally (taken into the body by mouth) or parenterally (taken into the body other than by mouth) administered substance which serves health, ergogenic, growth, or other bodily processes which food alone either cannot accomplish or cannot accomplish as efficiently is referred to as a supplement. Supplements can be nutritional or non-nutritional in nature. The traditionally identified classifications of supplements are health foods, additives, herbals (botanicals), nutriceuticals (engineered foods), micronutrients, macronutrients, adaptogens (bodily adaptation enhancers), ergogenic (work enhancing) compounds and anabolic (growth enhancing) compounds. See also nutriceutical. supination: Assuming a horizontal position facing upward. In the case of the hand, it also means turning the palm to face forward. The opposite of pronation. supinated grip: Grip in which the palm is facing upwards toward the ceiling. superset: Alternating back and forth between two exercises until the prescribed number of sets is completed. The two exercises generally involve a protagonist and antagonist (e.g., the biceps and triceps, or the chest and upper back); however, common usage of the term also can mean any two exercises alternated with one another. supercompensation: The post training period during which the trained function/parameter has a higher performance capacity than it did prior to the training period. submaximal GXT: A graded exercise test performed on a bicycle. This test gives an accurate estimate of an individual’s aerobic fitness level, allowing for comparison between the individual’s cardiovascular fitness to others in their age group. submaximal: Less than maximum. Submaximal exercise requires less than one’s maximum oxygen uptake, heart rate, or anaerobic power. Usually refers to intensity of the exercise, but may be used to refer to duration. stroke volume: The volume of blood pumped out of the heart into the circulatory system by the left ventricle in one contraction. stroke: Occurs when the blood supply to part of your brain is interrupted or severely reduced, depriving brain tissue of oxygen and nutrients. striations: Grooves or ridge marks of muscles’ individual myofibrils visible through the skin, and resulting from both hypertrophy training and extremely low subcutaneous fat deposits; the ultimate degree of muscle definition. stretching: Lengthening a muscle to its maximum extension; moving a joint to the limits of its extension. stretch reflex: A built-in protective function of the neuromuscular system in the muscle spindle that prevents overextension and serious injury to muscles and tendons. stressors: External stimulus or a events that cause stress to an organism. stress test: See graded exercise test. stress management: A group of skills for dealing with stresses imposed on an individual without suffering psychological distress and/or physical disorders. stress fracture: A partial or complete fracture of a bone because of the remodeling process’s inability to keep up with the effects of continual, rhythmic, nonviolent stresses on the bone. See also overuse. stress: The general physical and psychological response of an individual to any real or perceived adverse stimulus, internal or external, that tends to disturb the individual’s homeostasis. Stress that is excessive or reacted to inappropriately, may cause disorders. strength training: Using resistance weight training to build maximum muscle force is the traditional way of defining the practice of strength training. However, a more global definition would account for the metabolic circumstances under which force is being applied (i.e., the energy contribution from ATP/CP, glycolytic or oxidative sources). strength curve: A graphical representation of how the human body generates and applies force in a specific direction. strength: 1) Strength is the ability to contract the muscles with maximum force, given constraints stemming from the following: Structural/anatomical factors; Physiological/biochemical factors; Psychoneural/psychosocial factors; External/ environmental factors. 2) the ability to exert musculoskeletal force against an external object (such as a barbell, the ground, or an opponent). strain: A stretching or tearing of a musculotendinous unit. Degrees of severity include firstdegree, stretching of the unit; second-degree, partial tearing of the unit; third-degree, complete disruption of the unit. straight sets: Groups of repetitions (sets) interrupted by only brief pauses (30-90 seconds). storage fat: Represents the energy reserve that accumulates as adipose tissue beneath the skin and in visceral depots, averaging 12% body mass for men and 15% body mass for women. steady state: When oxygen intake meets the body’s demands during exercise. static stretching: Means a stretch is held in a challenging but comfortable position for a period of time, usually somewhere between 10 to 30 seconds. static contraction: A type of training that focuses on a way of developing the most muscle mass and strength through the smallest amount of motion and time in the gym. starting strength: The ability to recruit as many motor units (MU’s) as possible instantaneously at the start of a movement. starch: A polysaccharide made of glucose linked together. The body must convert starch into glucose which can be utilized for immediate energy or converted to glycogen and stored in the liver for later energy needs. It exists throughout the vegetable kingdom, its chief commercial sources being the cereals and potatoes. stabilizer: Muscle that steadies or holds a body part in place. stabilization: The act of being stable or balanced. stability: The ability to maintain a balanced state. squats: An upper leg and hip exercise usually performed with a barbell resting on the shoulders. A deep knee bend is performed; the squatter then returns to an erect standing position. There are several methods of squatting, each having its own unique advantages and disadvantages. The squat is also one of the three lifts contested in the sport of powerlifting. squamous epithelium: Epithelium consisting of one or more cell layers, the most superficial of which is composed of flat, scale-like or plate-like cells. sprain: A stretching or tearing of ligaments. Severity ratings of sprains are first-degree, partial tearing; third-degree, complete tearing. sports medicine: An area of medical practice concerned with the treatment of injuries resulting from athletic activities. spinal nerves: The 31 pairs of nerves radiating outward from the spinal cord which relay impulses to and from the skeletal muscles. speed strength: The ability of the neuromuscular system to produce the greatest possible impulse in the shortest possible time. It is defined in work divided by time, where work is defined as force x distance. specificity of training: The fact that the effects of training are specific to the manner in which the training is conducted and the activity employed as a training stimulus. specific strength: A material’s strength (force per unit area at failure) divided by its density. spasm: The involuntary contraction of a muscle or muscle group in a sudden, violent manner. somatotype: A category to which people are assigned according to the extent to which their bodily physique conforms to a basic type (usually endomorphic, mesomorphic, or ectomorphic). somatic system: System responsible for voluntary action. soluble fiber: Fiber that dissolves in water and attracts water to form a gel, which slows down digestion. soluble: Able to be dissolved, especially in water. sodium: An essential mineral for proper growth and nerve and muscle tissue function. A diet high in salt (40% of salt is sodium) causes a potassium imbalance and is associated with high blood pressure. No RDA. Dietary sources: salt, shellfish, celery, beets, artichokes. snatch: Olympic lift where weight is lifted from floor to overhead (with arms extended) in one movement. smooth muscle: Involuntary muscle tissue found in the walls of almost every organ of the body. small calories(cal): Represent the amount of heat required to raise the temperature of one gram of water by 1 degree centigrade. slow-twitch (type I) muscle fibers: Muscle fibers that help enable lower intensity, higher endurance movements such as distance running. Characterized by its slow speed of contraction and a high capacity for aerobic glycolysis. sliding filament theory: Theory stating that a myofibril contracts by the actin and myosin filaments sliding over each other. sleep apnea: A common disorder in which you have one or more pauses in breathing or shallow breaths while you sleep. skeletal system: System of the body consisting of bone and cartilage that supports and protects the body. skeletal muscle: Muscle that attaches to the skeletal system and causes body movement by a shortening or pulling action against its bony attachment. size principle of fiber recruitment: Principle stating that motor units are recruited in order according to their recruitment thresholds and firing rates. simple diffusion: Refers to a process whereby a substance passes through a membrane without the aid of an intermediary such as a integral membrane protein. simple carbohydrates: Monosaccharides and disaccharides occurring naturally in fruits, vegetables, and dairy products. Some examples of simple carbohydrates are glucose, galactose, and fructose—all of which are monosaccharides—and sucrose, lactose, and maltose—all of which are disaccharides. Most simple carbohydrates elevate blood sugar levels rapidly, providing “instant energy,” which is quickly utilized and dissipated. Fructose is an exception. Additionally, refined sources of simple carbohydrates, such as candy, contribute only calories to the diet. These “empty calories” are often consumed in place of foods which would provide important nutrients in addition to the energy. shin splints: Pain in the front of the lower leg from inflammation of muscle and tendon tissue caused by overuse. See also overuse. set: A group of repetitions of an exercise movement done consecutively, without rest, until a given number or momentary exhaustion is reached. See also repetition. serum testosterone: The principal male sex hormone and an anabolic steroid. In men, testosterone plays a key role in the development of male reproductive tissues such as the testis and prostate as well as promoting secondary sexual characteristics such as increased muscle, bone mass, and the growth of body hair. self-myofascial release (SMR): A soft tissue therapy for the treatment of skeletal muscle immobility and pain. This alternative medicine therapy aims to relax contracted muscles, improve blood and lymphatic circulation, and stimulate the stretch reflex in muscles. sedentary: Characterized by much sitting and little physical activity that might produce significant fitness benefits. secondary risk factor: A risk factor that acts when certain other risk factors are present. See also primary risk factor, risk factor. second-class lever: A lever in which the load lies between the fulcrum and the effort. screening: Comparing individuals to set criteria for inclusion in a fitness program or for referral to medical evaluation. scoliosis: A spinal disorder in which there is a sideways curve to the spine. The curve is often Sshaped or C-shaped. saturated fatty acids: Fat molecules that have no double bonds between carbon molecules because they are saturated with hydrogen molecules. Thus the chain of a saturated fatty acid contains no double bond. The saturated fatty acids are more slowly metabolized by the body than are the unsaturated fatty acids. Saturated fatty acids include acetic acid, myristic acid, palmitic acid, and steric acid. These acids come primarily from animal sources, with the exception of coconut oil, and are usually solid at room temperature. In the case of vegetable shortening and margarine, oil products have undergone a process called “hydrogenation,” in which the unsaturated oils are converted to a more solid form. Other principal sources of saturated fats are milk products and eggs. saturated fat: Dietary fat from primarily animal sources. Excessive consumption is the major dietary contributor to total blood cholesterol levels and is linked to increased risk for coronary heart disease. satellite cells: Skeletal muscle satellite cells are quiescent mononucleated myogenic cells located between the sarcolemma and basement membrane of terminally-differentiated muscle fibres. These are normally quiescent in adult muscle, but act as a reserve population of cells, able to proliferate in response to injury and give rise to regenerated muscle and to more satellite cells. sartorius: The longest muscle in the body, involved in the movement of the thigh at the hip joint. sarcoplasmic reticulum: The specialized endoplasmic reticulum of cardiac muscle and skeletal striated muscle that functions especially as a storage and release area for calcium. sarcoplasm: Jellylike intracellular fluid found in the muscle fiber. sarcomere: A structural unit of a myofibril in striated muscle, consisting of a dark band and the nearer half of each adjacent pale band sarcolemma: The fine transparent tubular sheath that envelops the fibers of skeletal muscles. sagittal (anteroposterior) plane: Separates the body into right and left sections. rotator cuff: A band of four muscles that hold the arm in the shoulder joint. rotation: Circular movement of a body segment about a long axis. Rolfing: A massage technique aimed at the vertical realignment of the body, and therefore deep enough to release muscular tension at skeletal level. It can contribute to the relief of longstanding tension and neuroses. RM: Acronym for “repetitions maximum.” Thus, for example, 5RM stands for the maximum amount of weight you can perform for five repetitions. risk factor: A behavior, characteristic, symptom, or sign that is associated with an increased risk of developing a health problem. Example: Smoking is a risk factor for lung cancer and coronary heart disease. See also primary risk factor, secondary risk factor. ripped: Slang meaning extremely visible muscularity resulting from both hypertrophy and subcutaneous fat removal. retinopathy: Disease of the retina that results in impairment or loss of vision. retest: A repetition of a given test after passage of time, usually to assess the progress made in an exercise program. resting metabolic rate (RMR): The amount of energy (calories) required to efficiently perform vital bodily functions such as respiration, organ function and heart rate while the body is awake, but at rest. resting inertia: An object is at rest, it will stay at rest unless acted upon by some outside force resting heart rate (RHR): The number of times the heart beats in one minute: 72 beats per minute for the average adult. rest interval: Pause between sets of an exercise which allows muscles to recover partially before beginning next set. response: An immediate, short-term change in physiological functions (such as heart-rate or respiration) brought on by exercise. See also adaptation. respiratory system: System consisting of the lungs and air passageways, which supplies oxygen to the body and removes carbon dioxide. respiratory quotient (RQ): A method of determining the “fuel mix” being used giving us a way to measure the relative amounts of fats, carbohydrates, and proteins being burned for energy. respiration: Exchange of oxygen and carbon dioxide between the atmosphere and the cells of the body. Includes ventilation (breathing), exchange of gasses to and from the blood in the lungs, transportation of the gasses in the blood, the taking in and utilizing of oxygen, and the elimination of waste products by the cells. See also expiration, inspiration, ventilation. resistant starch: Starch and starch degradation products that escape from digestion in the small intestine of healthy individuals. resistance bands: An elastic band used for strength training. They are also commonly used in physical therapy, specifically by convalescents of muscular injuries. resistance: The amount of weight used in each set of an exercise, or the force which a muscle is required to work against. residual volume: The remainder of the air in the lungs after the usable lung volume has been measured. Must be calculated in the formula for determining body composition through underwater weighing. reproductive system: System consisting of gonads, associated ducts, and external genitals concerned with sexual reproduction. repetition: An individual-completed exercise movement. Repetitions are usually done in multiples. See also one repetition maximum, set. repetitive overuse syndrome (ROS): Usually defined as work and/or activity-related symptoms caused by repetitive tasks, forceful exertions, vibrations, mechanical compression (impact on hard surfaces), sustained or awkward poses, and excessive use of the body. Results from improper muscle balance around the joints. renal: Pertaining to the kidney. REM sleep: A kind of sleep that occurs at intervals during the night and is characterized by rapid eye movements, more dreaming and bodily movement, and faster pulse and breathing. relative work intensity: Refers to the fact that work (exercise) is rated by the ratio of the energy required for the work to your resting (or basal) requirement rehabilitation: A branch of medicine that aims to enhance and restore functional ability and quality of life to those with physical impairments or disabilities. recuperation: A physiological process involving full body and muscle recovery and subsequent muscle growth during a rest period between training sessions. rectus femoris: The long, straight muscle in the front of the thigh which attaches to the knee cap. Part of the quadriceps muscle group. recruitment: Activation of motor units; the greater the resistance encountered, the greater will be the rectus recruitment necessary to overcome its inertia. reciprocal innervation: Innervation so that the contraction of a muscle or set of muscles (as of a joint) is accompanied by the simultaneous inhibition of an antagonistic muscle or set of muscles. RDA (Recommended Daily Dietary Allowances): Estimates established by the National Research Council of the National Academy of Sciences for nutritional needs necessary for prevention of nutrient depletion in healthy people. Does not take into account altered requirements due to sickness, injury, physical or mental stress, use of medications or drugs, nor compensate for the nutrient losses that occur during processing and preparation of food. RDA standards do not apply to athletes, who have extraordinary nutrient needs. While they were designed to meet the needs of a majority of people, RDAs are nonetheless far too low for serious athletes and even for fitness enthusiasts who exercise regularly. (See ODA: Optimal Daily Allowances) ratings of perceived exertion (RPE): A rating scale ranging from six to 20 that gives an indication of your workout intensity level. range of motion (ROM): The movement of a joint from full flexion to full extension. radial pulse: The pulse at the wrist. quadriceps: A muscle group at the front of the thigh connected to a common tendon that surrounds the knee cap and attaches to the tibia (lower leg bone). The individual muscles are the rectus femoris, vastus intermedius, vastus lateralis, and vastus medialis. Acts to extend the lower leg. Q-T syndrome: A rare inherited or acquired heart condition in which delayed repolarization of the heart following a heartbeat increases the risk of episodes of torsades de pointes. pyruvic acid: The end product of the glycolytic pathway. This three-carbon metabolite is an important junction point for two reasons: it is the gateway to the final common energy-producing pathway, the Krebs cycle; and it provides acetyl coenzyme A (acetyl CoA), through which fatty acids, and in turn fat, are produced from glucose. Pyruvic acid converts to lactic acid as needed. Pyruvic acid increases in quantity in the blood and tissues in thiamine (vitamin B-1) deficiency. Thiamine is essential for its oxidation. pyruvate: A byproduct of glycolysis. pyramid training: A training protocol incorporating an upward- then-downward progression in weight, rep-per-rep or set-per-set. pumping iron: Slang for lifting weights, a phrase used since the 1950s. pumped: Slang term to describe the tightness in a muscle made large through exercise. The pumped sensation results from blood engorgement and lactic acid accumulation in the exercised muscle. pulmonary: Pertaining to the lungs. pulmonary (ventilatory) capacity: The efficiency of gas exchange in the lungs. psychomotor: Of or relating to the origination of movement in conscious mental activity. protein receptors: An intracellular protein or protein fraction having a high specific affinity for binding agents known to stimulate cellular activity, such as a steroid hormone or cyclic AMP. protein: Any of a class of nitrogenous organic compounds that consist of large molecules composed of one or more long chains of amino acids and are an essential part of all living organisms, especially as structural components of body tissues such as muscle, hair, collagen, etc., and as enzymes and antibodies. protease: A category of enzymes which attack specific bonds between amino acids and proteins. The proteases break amino acid bonds to split up the protein molecule into smaller pieces of lined amino acids. Examples of proteases are renin and pepsin; these enzymes can be found in animals. Rennin is used in the thickening of milk and is isolated from the stomach of the calf; pepsin is found in the gastric juices of humans and other animals where it breaks down proteins at specific places. proprioceptor: Specialized sensory receptors located in tendons and muscles sensitive to stretch, tension, pressure, and position of the body. Proprioceptors include muscle spindles and Golgi tendon organs. proprioceptive neuromuscular facilitation (PNF): A set of stretching techniques commonly used in clinical environments to enhance both active and passive range of motion with the ultimate goal being to optimize motor performance and rehabilitation. Example: The contraction of an agonist muscle sends inhibiting signals that relax the antagonist muscle so that it is easier to stretch. (Term was once applied to a very specific therapeutic technique, but now is being widely applied to stretch techniques such as slow-reversal-hold, contract-relax, and hold-relax.) proprioceptive feedback: Relating to stimuli that are produced and perceived within an organism, especially those connected with the position and movement of the body. pronation: Assuming a facedown position. Of the hand, turning the palm backward or downward. Of the foot, lowering the inner (medial) side of the foot so as to flatten the arch. The opposite of supination. pronated grip: To turn or rotate (the hand or forearm) so that the palm faces down or back proliferative-injection therapy: A treatment of tissue with the injection of an irritant solution into a joint space, weakened ligament, or tendon insertion to relieve pain. progressive resistance exercise: Exercise in which the amount of resistance is increased to further stress the muscle after it has become accustomed to handling a lesser resistance. proboitics: A microorganism introduced into the body for its beneficial qualities. prime mover (agonist): Denoting a muscle in a state of contraction, with reference to its opposing muscle, or antagonist. primary risk factor: A risk factor that is strong enough to operate independently, without the presence of other risk factors. preload: The stretching of a muscle prior to contracting it, thereby providing both a “stretch reflex” and a viscoelastic component, adding to the total force output. prebiotics: A nondigestible food ingredient that promotes the growth of beneficial microorganisms in the intestines. powerlifts: Three lifts contested in the sport of powerlifting: the squat, bench press, and deadlift. Powerlifting was first organized in the USA in the early 60s from the “odd lifts” competitions which used to be part of almost all bodybuilding and weightlifting competitions. Of the over 40 odd lifts contested, these three lifts were chosen as being the most representative test of total body limit strength. power training: System of weight training using low repetitions and explosive movements with heavy weights. power: In physics and in most sports, power is defined as the work done in a unit of time. Measured by the formula—work equals force times distance divided by time. A combination of strength and speed. posture: the way the body holds itself when sitting, standing, lying down, or moving. post-exercise muscle soreness (PEMS): The sensation of discomfort or pain in the skeletal muscles following physical activity, usually eccentric, to which an individual is not accustomed. polyunsaturated fat: Dietary fat whose molecules have more than one double bond open to receive more hydrogen. Found in safflower oil, corn oil, soybeans, sesame seeds, sunflower seeds. See also monounsaturated fat, saturated fat, unsaturated fat. polysaturated fatty acids: Fatty acids that contain more than one double bond in their backbone. point of application: Refers to where the force is applied on the body or implement being used. plyometric: Exercises in which muscles exert maximum force in short intervals of time, with the goal of increasing both speed and power. An example is jumping down from a bench and immediately springing back up. platelet: Cytoplasmic body found in the blood plasma that functions to promote blood clotting. plasma: The fluid portion of blood. plantarflexion: Extension of the ankle, pointing of the foot and toes. phytonutrients: A substance found in certain plants which is believed to be beneficial to human health and help prevent various diseases. phytochemicals: A chemical found in and obtained from plants that is biologically active but not nutritive phytates: The principal storage form of phosphorus in many plant tissues, especially bran and seeds. physiology: The science concerned with the normal vital processes of animal and vegetable organisms. physical work capacity (PWC): An exercise test that measures the amount of work done at a given, submaximal heart rate. The work is measured in oxygen uptake, kilopond meters per minute, or other units, and can be used to estimate maximal heart rate and oxygen uptake. Less accurate, but safer and less expensive than the graded exercise test. physical fitness: The physiological contribution to wellness through exercise and nutrition behaviors that maintain high aerobic capacity, balanced body composition, and adequate strength and flexibility to minimize risk of chronic health problems and to enhance the enjoyment of life. physical conditioning: A program of regular, sustained exercise to increase or maintain levels of strength, flexibility, aerobic capacity, and body composition consistent with health, fitness, or (especially) athletic objectives. phosphocreatine (PCr): A phosphate ester of creatine found in vertebrate muscle, where it serves to store phosphates to provide energy for muscular contraction. phlebitis: The inflammation of a vein, usually in the legs. It most commonly occurs in superficial veins. Phlebitis often occurs in conjunction with thrombosis and is then called “thrombophlebitis” or “superficial thrombophlebitis”. pH: A measure of acidity relating to the hydrogen ion (H+) concentration. A pH of 7.0 is neutral; acidity increases with lower numbers and alkalinity increases with higher numbers. Body fluids have a pH of about 7.3. peripheral nervous system (PNS): Relays messages from the CNS to the body (the efferent system) and relays messages to the CNS (the afferent system) from the body. peripheral heart action training (PHAT): A form of resistance training performed in a circuit fashion (or little rest between exercises). The peripheral heart action training system requires you to perform multiple exercises in rapid succession, but alternating between upper and lower body exercises. This helps facilitate circulation to various muscles and helps you burn extra calories compared to traditional weight lifting. periodization or “periodized training”: A phrase which refers to how one’s training is broken down into discreet time periods called “macrocycles, mesocycles and microcycles.” peptide chain (polypeptide chain): A chain of amino acids joined together through peptide bonds. peptide: Any member of a class of compounds of low molecular weight which yield two or more amino acids on hydrolysis. Formed by loss of water from the NH2 and COOH groups of adjacent amino acids, they are known as di-, tri-, tetra- (etc.) peptides, depending on the number of amino acids in the molecule. Peptides (“polypeptides”) form the constituent parts of proteins. pecs: Slang for pectoral muscles of the chest. peak heart rate: The highest heart rate reached during a work session. peak contraction: Exercising a muscle until it cramps by using shortened movements. patellofemoral pain syndrome (PFPS): Pain in the front of the knee that frequently occurs in teenagers, manual laborers, and athletes. It sometimes is caused by wearing down, roughening, or softening of the cartilage under the kneecap. passive range of motion (ROM): The range of motion through which a therapist or equipment can move the joint through the range of motion with no effort from the patient. partial reps: Performing an exercise without going through a complete range of motion. Exercise mythology has it that one must exercise a muscle through a full range of motion of the joint upon which the muscle acts in order not to become “muscle bound” and to derive maximum strength and growth. In reality, partial movements often provide better overload because more weight can be moved. parcourse training: A concept borrowed from outdoor parks and applied to the gym during sports-specific phase of foundation training for aerobic athletes. Involves the performance of aerobic activities: jogging, skipping rope, straddle jumping, bicycle ergometer—between exercises of a weight training routine. parasympathetic overtraining: A serious end-stage of overtraining associated with the exhaustion of neurological and hormonal factors, typically with serious physical, chemical, or mental injuries. palpatations: A perceived abnormality of the heartbeat characterized by awareness of heart muscle contractions in the chest: hard beats, fast beats, irregular beats, and/or pauses. Pacinian corpuscles: An encapsulated ending of a sensory nerve that acts as a receptor for pressure and vibration. pacemaker: An artificial device for stimulating the heart muscle and regulating its contractions. oxygen uptake: The amount of oxygen intake used up at the cellular level during exercise. Can be measured by determining the amount of oxygen exhaled as compared to the amount inhaled or estimated by indirect means. oxygen deficit: Occurs as you begin to exercise when your intake of oxygen does not immediately meet your demands. Becomes oxygen debt at end of exercise. oxygen debt: Inspired oxygen during recovery phase from exercise that is in excess of the body’s resting needs. In intense endurance activities, oxygen debt refers to the amount of oxygen that is “owed” to the system to oxidize lactic acid buildup. One’s tolerance for an accumulated debt is generally proportional to the level of fitness. oxygen consumption: See oxygen uptake. oxygen (O2): The essential element in the respiration process to sustain life. The colorless, odorless gas makes up about 20 percent of the air, by weight at sea level. oxidative sports: Sports such as long distance running or cycling wherein oxygen must be present to allow movement to continue (see ATP/CP sports and glycolytic sports). oxidative pathway: A metabolic process in which oxygen combines with lactic acid, resynthesizing glycogen to produce energy aerobically. oxidation: The chemical act of combining with oxygen or of removing hydrogen. oxalates: Any salt or ester of oxalic acid, occurring in plants, especially spinach, rhubarb, and certain other vegetables and nuts, and capable of forming an insoluble salt with calcium and interfering with its absorption by the body. overweight: Above a weight considered normal or desirable. People with Body Mass Indexes of 25 to 29.9 are considered overweight. overuse syndrome: Injury resulting from overtraining. overuse: Excessive repeated exertion or shock which results in injuries such as stress fractures of bones or inflammation of muscles and tendons. overtraining: Excessive training, principally of the eccentric contraction phase of lifting weights or running. Can cause injuries, loss of body weight, insomnia, depression, chronic muscle soreness, and retard workout recovery. overreaching: An accumulation of training and/or non-training stress resulting in a short-term decrement in performance capacity with or without related physiological and psychological signs and symptoms of overtraining in which restoration of performance capacity may take from several days to several weeks. overload principle: States that a greater than normal stress or load on the body is required for training adaptation to take place. overload: Subjecting a part of the body to efforts greater than it is accustomed to, in order to elicit a training response. Increases may be in intensity or duration. outcomes-based: Basing nutritional decisions on specific, measurable outcomes rather than nebulous definitions of what’s “good” or “correct. osteoarthritis: A noninflammatory joint disease of older persons. The cartilage in the joint wears down, and there is bone growth at the edges of the joints. Results in pain and stiffness, especially after prolonged exercise. ossification: The formation of bone. The turning of cartilage into bone (as in the joints). See also myositis ossificans, osteoarthritis. osmosis: The scientific process of transferring fluid between molecules. osmolarity: The concentration of a solution participating in osmosis (e.g., a sugar-water solution of high osmolarity is concentrated enough to draw water through the membranes of the digestive tract to dilute the sugar.) See also hypertonic, hypotonic. Osgood Schlatter’s Disease: An inflammation of the patellar ligament at the tibial tuberosity. It is characterized by a painful lump just below the knee and is most often seen in young adolescents. origin: The proximal attachment. The origin is generally considered the least movable part or the part that attaches closest to the midline (vertical center in the anatomical position) of the body. organs: A part of an organism that is typically self-contained and has a specific vital function, such as the heart or liver in humans. organism: The material structure of an individual life form. organelles: Any of a number of organized or specialized structures within a living cell. organ systems: A group of organs that work together to perform one or more functions. open grip: A grip position in which the thumb does not wrap around the bar. one repetition maximum (1RM): The maximum resistance with which a person can execute one repetition of an exercise movement. omega-6 fatty acids: A family of pro-inflammatory and anti-inflammatory polyunsaturated fatty acids that have in common a final carbon-carbon double bond in the n-6 position, that is, the sixth bond, counting from the methyl end. omega-3 fatty acids: An unsaturated fatty acid of a kind occurring chiefly in fish oils, with three double bonds at particular positions in the hydrocarbon chain. Olympic set: High-quality, precision-made set of weights used for competition. The bar is approximately 7’ long. All moving parts have either brass bushings or bearings. Plates are machined for accurate weight. Olympic lifts: The two weightlifting movements used in Olympic competitions: the snatch, and the clean and jerk. The military press was eliminated as a contested lift after the 1972 Olympics. See also weightlifting. obliques: Short for external and/or internal obliques, the muscles to either side of abdominals that rotate and flex the trunk. obesity: Excessive accumulation of body fat. People with BMIs of 30 and above are considered obese. nutrition: The programmatic use of nutrients. nutrients: Food and its specific elements and compounds that can be used by the body to build and maintain itself and to produce energy. Conventionally, this word refers to the macronutrients (water, protein, fats, carbohydrates) and the micronutrients (vitamins, minerals, and trace elements) that are essential for energy and growth. On a legal (FDA) level, it specifically excludes substances for which claims are made (legitimately or illegitimately) for amelioration, cure, or prevention of any disease entity or other clinical functions beyond growth and energy. nutrient density: Identifies the proportion of nutrients in foods, with terms such as nutrient-rich and micronutrient-dense referring to similar properties. nutrient deficiencies: An inadequate supply of essential nutrients (as vitamins and minerals) in the diet resulting in malnutrition or disease. nonlinear strength endurance: The ability to perform an activity with exceeding explosiveness over and over for an extended period of time. non-exercise activity thermogenesis (NEAT): Spontaneous physical activity, things like tapping feet and moving hands. neutralizer: When a muscle contracts to counteract an undesirable action of another muscle. neutral grip: Grip wherein the palms face each other. neurotransmitter: A chemical substance that is released at the end of a nerve fiber by the arrival of a nerve impulse and, by diffusing across the synapse or junction, causes the transfer of the impulse to another nerve fiber, a muscle fiber, or some other structure. neural adaptation: A change over time in the responsiveness of the sensory system to a constant stimulus. It is usually experienced as a change in the stimulus. nervous tissue: The main component of the nervous system, the brain and spinal cord of the central nervous system (CNS), and the branching peripheral nerves of the peripheral nervous system (PNS), which regulates and controls bodily functions and activity. nervous system: System comprised of brain, spinal cord, sense organs, and nerves. Regulates other systems. nerve impulse: A brief reversal of the membrane potential that sweeps along the membrane of a neuron. negative reps: An eccentric contraction. One or two partners assist in lifting a weight up to 20– 40% heavier than an individual could normally lift. Once hoisted to the extended position, the weight is slowly lowered without help. This type of exercise is extremely damaging to connective tissue and (according to the “cataclysmic” theory of overtraining) is the elemental factor in overtraining and cumulative microtrauma. nautilus: Variable resistance-type exercise machine which attempts to match the amount of resistance with the user’s force output. Arthur Jones, developer of Nautilus equipment in the 1970s, is considered one of the true pioneers of fitness technology. myxedema: Swelling of the skin and underlying tissues giving a waxy consistency, typical of patients with underactive thyroid glands. myositis ossificans: The deposit of bony materials in the muscle. Bruises from contact sports may result in this condition. Severe bruises should be iced, and evaluated by a physician. myositis: Inflammation of a skeletal muscle. myosin: Short, thick contractile filaments. The most abundant protein (68%) in muscle fiber. It is the main constituent of the thick contractile filaments which overlap with the thin actin filaments in the biochemical sequence that produces contractions. myoneural junction: The connection of a neuron to a muscle fiber. myoglobin: An iron-containing protein responsible for oxygen transport and storage in muscle tissue, similar to hemoglobin in blood. myofilaments: The elements of a muscle cell which comprise myofibrils that actually shorten (thereby providing contractile force) by sliding across one another via action of “cross bridges.” They are comprised of the proteins actin and myosin. myofibril: Tiny fibrils that make up a single muscle fiber which are the functional units within muscle fibers that cause contractions. The more you have, the greater your strength. Myofibrillarization—increasing myofibrils—is achieved with the use of heavy weight training. myocarditis: Inflammation of the heart muscle. myocardial infarction (MI): A common form of heart attack in which the blockage of a coronary artery causes the death of a part of the heart muscle. See also infarction. musculotendinous: Of, relating to, or affecting muscular and tendinous tissue. musculoskeletal system: Body system that consists of the bones, joints, connective tissue, and muscles. muscular tonus: A state of partial contraction present in a muscle in its passive st