Chapter 2 Flashcards
The Basics of Exercise Science
Human Movement
the kinetic chain made up of three primary systems: SKELETAL (bones/joints), MUSCULAR (ligaments, tendons, muscles, and fascia), and the NERVOUS (PNS and CNS).
CNS
Central Nervous System; made up of the spinal cord and brain.
PNS
Peripheral Nervous System; consists of nerves that connect the spinal cord and brain to the rest of the body.
Sensory Function
the ability of the NS to notice changes in the external or internal environment. ONE OF THE 3 MAIN FUNCTIONS OF THE NS.
Integrative Function
the ability that the NS has to interpret and analyze sensory info. (Allows for adequate decision making / producing the correct response)
Motor Function
the neuromuscular response to sensory info.
Three main functions of the Nervous System?
Sensory, Integrative, and Motor
Proprioception
the cumulative sensory input to the CNS from the mechanoreceptors that can sense limb movement and body position.
What does proprioception training improve?
Coordination, balance, and posture.
Neuron
the functional unit of the NS; allows communication with both the outside and internal environment.
___ form the core of the spinal cord, brain and peripheral ganglia that make up the NS.
Neurons
The three main parts of the neuron:
Cell body, axon, and dendrites.
Afferent / Sensory Neurons
type of nerve cell that conducts impulses to the CNS from a sense organ.
Efferent / Motor Neurons
type of nerve cell that sends impulses to glands, muscles, and other effectors; stimulates muscle contraction to initiate movement.
Interneurons
send nerve impulses between one another.
Mechanoreceptors
specialized receptors that respond to pressure inside of tissues and transmit signals through sensory nerves.
What are some of the forces that mechanoreceptors respond to?
motion, sound waves, pressure, stretching, and touch; can sense various distortions in the human body.
Muscle Spindles
sensory receptors that sit parallel to muscular fibers; able to detect the length of a muscle and how fast in changes length.
What is the purpose of the muscle spindle?
to help regulate the contraction of muscles by way of the stretch reflex mechanism to help prevent and protect over-stretching that could lead to muscular damage.
Golgi Tendon Organs
GTO; specialized sensory receptor found where tendons attach to skeletal muscle fibers; sense change is muscular tension and the rate of this change in tension.
What happens when you activate a GTO?
it will cause a muscle to relax; helps prevent injury from excess stress and contraction.
Joint Receptors
located around the joint capsule; able to sense extreme joint positions and send signals in order to prevent injuries by responding to acceleration, deceleration, and pressure at the joint.
What is the function of the Skeletal System?
provides the focus and shapes for our bodies as well as creates blood and stores minerals.
Provide protection for vital organs and a resting place for muscles.
Bones
Junctions for muscles, bones, and connective tissue where movement occurs.
Joints (Articulations)
Axial Skeleton
contains the rib cage, skull, and vertebral column; 80 bones total.
(“foundation”)
Appendicular Skeleton
consists of lower and upper extremities; 126 bones total.
“appendages/outer frame”
the process of formation and resorption of bone where the older bone is broken down and taken away by osteoclasts and new bone is made to replace it with osteoblasts.
Remodling
Osteoclasts
cells that help remove bone tissue
Osteoblasts
cells that help create new bone tissue
Epiphysis
located at the end of long bones; contains a large portion of the red marrow (production of RBCs). A main location for bone growth.
Diaphysis
the long portion of the bone; considered the shaft. Compact and strong.
Epiphyseal Plate
area of the long bone that connects the epiphysis to the diaphysis; dividing layer of cartilage in cells that grow lengthwise to create the diaphysis.
Periosteum
dense and fibrous outer layer where muscles attach with a more delicate layer inside that can create bone.
Medullary Cavity
location where bone marrow is stored, blood cell formation occurs. Small cavity located in the shaft of the bone.
Articular Cartilage / Hyaline
the inelastic, flexible yet firm connective tissue located at the end of bones at the joint.
Depressions
Flat areas of a bone.
Processes
Part of the bone where ligaments in muscle attach.
How many bones are in the lumbar (lower) part of the vertebral column?
5
How many bones are in the thoracic (middle) part of the vertebral column?
12
How many bones are in the cervical (upper) part of the vertebral column?
7
Arthrokinematics
the description of joint surfaces when bones are put through a range of motion.
Synovial Joints
joined bones that have a fibrous joint capsule; produce synovial fluid (looks like egg whites) to protect the joint.
Non-Synovial Joints
joints that are non-movable and exclude the joint cartilage, capsule, and ligaments.
Approximately what percentage of joints in the human body are synovial joints?
~80%
Where are most of the non-synovial joints found?
in the distal joint of the fibula and tibia as well as the skull.
Ligaments
connects bones to other bones; joint support.
Epimysium
outside layer of muscular connective tissue.
Perimysium
middle layer of muscular connective tissue; encompasses the muscle fascicle.
Endomysium
deepest later of muscular connective tissue; covers the muscle fibers.
Tendon
connects skeletal muscles to bone with a band of white, inelastic, dense, tough band of tissue.
Sarcomere
the functional unit of a muscle that produces contractions; comprised of ACTIN and MYSOIN.
What is the repeating section of a muscle?
the sarcomeres
Neural Activation
the process of NS activation of a muscle fiber by the means of the neuromuscular junction
Motor Unit
the motor neuron + all of the muscle fibers it innervates.
Type I Fibers
smaller, produce less power, receive more oxygen, more mitochondrial dense.
Type II Fibers
less oxygen delivery, short-term contractions, produce more force and power, larger.
What fibers are also known as slow twitch or “endurance” fibers?
Type I
What fibers are also know as fast twitch fibers?
Type II
Type IIx
have low oxidative capacity / quick to fatigue.
Type IIa
higher oxidative capacity; will fatigue slower that type IIx.
Which fibers are also known as “intermediate fast twitch muscle fibers?”
Type IIa
Excitation-Contraction Coupling
the process by which the NS stimulates a muscle in the body to contract.
What is another name for excitation-contraction coupling?
The “sliding filament theory”
What is the process of the sliding filament theory, or “excitation-contraction coupling?”
- ACH released; binds with receptors that begin an action potential down the T Tubula.
- Action potential initiates Ca2+ (calcium) release.
- Ca2+ bind with troponin; this stops the blocking action of tribal myosin that exposes the binding site for actin.
- Contraction - myosin cross brides alternately detach and attach to actin; brings the filaments closer to the middle of the sarcomere (Need ATP in order for actin and myosin to detach).
- Tropomyosin returns to its location and covers the actin active site; contractions cease.
Agonist
the prime mover
Synergist
assists and helps prime mover
Stabilizers
help stabilize joint during movement
Antagonist
these muscles relax in order to permit the prime mover to work
