Ch 2 - Exercise Science Flashcards
Human movement system
combination of nervous, muscular, and skeletal systems
CNS
brain and spinal cord
PNS
cranial and sacral nerves connecting CNS to the rest of the body
Sensory function
ability of nervous system to sense changes in internal or external environment
Integrative function
ability of nervous system to analyze and interpret sensory info
Motor function
neuromuscular response to sensory info
Sensory (afferent) neurons
transmit nerve impulses from effector sites to CNS
Interneurons
transmit nerve impulses from one neuron to another
Motor (efferent) neurons
transmit nerve impulses from CNS to effector sites
Somatic nervous system
responsible for voluntary control of movement
Autonomic nervous system
responsible for involuntary systems
Sympathetic nervous system
supports activity
Parasympathetic nervous system
supports rest and recovery
Mechanoreceptors
sensory receptors that sense distortion in body tissue
Muscle spindles
SRs sensitive to changes in length; prevent overstretching by telling muscles to contract
Golgi tendon organs
SRs sensitive to changes in tension; prevent excess stress by telling muscles to relax
Joint receptors
SRs sensitive to pressure, acceleration, and deceleration of joints; signal extreme joint positions
Axial skeleton
skull, ribcage, and vertebral column
Appendicular skeleton
upper and lower extremities and shoulder and pelvic girdle
Remodeling
resorption and formation of bone
Epiphysis
end of long bones
Diaphysis
shaft of long bones
Epiphyseal plate
connects epiphysis to diaphysis; where growth occurs
Periosteum
membrane of connective tissue wrapping bones, except articulating surfaces
Medullar cavity
where bone marrow is stored
Hyaline cartilege
covers articular surfaces of bones
Surface markings
structures in bones for stability and muscle attachment
Arthrokinematics
joint motion
Joint motions (3)
roll, slide, spin
Synovial joints
joints held together by a joint capsule and ligaments
Joint types (6)
gliding, condyloid, hinge, saddle, pivot, ball and socket
Ligaments
connective tissue that connects one bone to another
Epimysium
connective tissue surrounding muscle
Perimysium
connective tissue surrounding fascicles
Endomysium
connective tissue surrounding individual muscle fibers (deepest layer)
Tendons
connective tissue that connects muscle and bone
Sarcolemma
plasma membrane that encases muscle fibers
Sarcomere
functional unit of muscle that produces contraction; made of repeating sections of actin (thin) and myosin (thick) myofilaments
Neural activation
muscle contraction generated by neural stimulation
Motor unit
one neuron and the muscle fibers it connects
Neurotransmitters
chemical messengers that cross the NM junction to transmit electrical impulses from nerves to muscles
Acetylcholine (ACh)
neurotrasmitter that stimulates mucles to contract
Type I muscle fibers
slow-twitch fibers; more endurance; used for stability and posture
Type II muscle fibers
fast-twitch fibers; more power; used for movement
Type IIx muscle fibers
fast-twitch fibers; lower ability to use oxygen and fatigue faster than type IIa
Type IIa muscle fibers
intermediate fast-twitch fibers; combination of type I and type II
Primary glands (4)
hypothalamus, pituitary, thyroid, adrenals
Insulin
hormone that helps regulate energy and glucose metabolism; causes cells to store glucose as glycogen
Glucogen
opposite effect of insulin; causes cells to convert glycogen into glucose and release it into bloodstream
Catecholamines
epinephrine (adrenaline) and norepinephrine; prepare body for activity; part of fight or flight response
Sliding filament theory
thin and thick muscle filaments slide past each other to shorten sarcomeres and thus shorten the muscle and produce force
