 Active range of motion – Portion of the total range of motion through which a joint can be moved by an active muscle contraction  Aerobic – An activity that requires oxygen  Agonist – The muscle that is contracting to produce movement  Antagonist – The muscle that is being stretched when the agonist contacts  Anaerobic – An activity that does not require oxygen  Atrophy – A decrease in the size of a muscle

 Ballistic stretch – Exercise in which body momentum is used to force muscle groups into as much extensibility as can be tolerated. This may also induce muscle tears as a result of misjudging the stretch tolerance of the body tissues or failing to control the force of the body momentum.  Cardiorespiratory endurance – The ability to perform whole- body large muscle activities for extended periods of time  Circuit training – Involves the use of a series of exercise stations that consist of various combinations of weight training, flexibility, calisthenics, and brief aerobic exercises  Closed kinetic chain exercises – Exercises in which the foot or hand is in a weight bearing position on the ground or some other object  Concentric contraction (Positive resistance) – A muscle contraction in which the muscle is shortened during contraction

 Core – Made up of the lumbo-pelvic-hip complex where the center of gravity is located and all movement begins.  Eccentric contraction (Negative resistance) – The muscle lengthens during a contraction  Endurance – The ability of the body to undergo prolonged activity  Fartlek training – Means “speed play” and involves running for a specific period of time without specific criteria placed on pace and speed  Flexibility – The range of motion (ROM) of a specific joint influenced by bony structures and the physiological characteristics of muscles, tendons, ligaments, and other collagenous tissues around the joint

 Functional Strength Training – The use of integrated exercises to improve functional movement patterns in terms of both increased strength, as well as improved neuromuscular control and core stabilization.  Hypertrophy – An increase in muscle size  Interval training – Involves alternating periods of relatively intense work and active recovery  Isokinetic contraction – A muscle contraction in which the length of the muscle is changing while the contraction is performed at a constant velocity  Isometric contraction – A muscle contraction that generates energy (in the form of heat) with no change in length of the muscle or in the angle of the joint at which the contraction takes place. A "static contraction"

 Isotonic contraction – A "dynamic contraction" that either involves a shortening (concentric) or a lengthening (eccentric) of the muscle through a complete range of motion  Muscular endurance – The ability to perform repetitive muscular contractions against some resistance  Muscular strength – The ability of a muscle to generate force  Muscular power – The ability to generate force rapidly  Open kinetic chain exercise – The foot or hand is not in contact with the ground or other object while performing exercises

 Overload principle – Training is performed with a progressively increased load or resistance at a near-maximal rate  Passive range of motion – Portion of the total range of motion through which a joint can be moved without a muscle contraction  Periodization – Conditioning principle that allows athletes to train year round with less risk of injury  Plyometric exercise – A type of exercise that produces an isometric-type overload using the stretch reflex