NASM CPT 7th Edition (Chapter 5)

Human Movement System (HMS)

The collective components and structures that work together to move the body: muscular, skeletal, and nervous systems

Kinetic Chain

A concept that describes the human body as a chain of interdependent links that work together to perform movement

Nervous System

A network of specialized cells called neurons that transmit and coordinate signals, providing a communication network within the human body

Neuron

A specialized cell that is the functional unit of the nervous system

Nucleus

Cellular structure or organelle that contains the majority of the cell's genetic material in the form of chromosomes

Organelles

Tiny cellular structures that perform specific functions within a cell. Examples include nuclei, mitochondria, lysosomes, ribosomes, and the endoplasmic reticulum

Mitochondria

The parts of the cell that use nutrients to create energy for the cell; commonly known as the powerhouses of the cell

Effector Sites

A part of the body, such as a muscle or organ, that receives a signal from a neuron to produce a physiological response

Electrolytes

Minerals that have an electrical charge to help transmit nerve impulses throughout the body, such as sodium, potassium, and magnesium

Central Nervous System (CNS)

A division of the nervous system that includes the brain and spinal cord

Peripheral Nervous System (PNS)

Nerves that connect the rest of the body to the central nervous system

Afferent Pathway

Sensory pathway that relays information to the central nervous system

Efferent Pathway

A motor pathway that relays information from the central nervous system to the rest of the body

Interneurons

Neurons located within the spinal cord and brain that transmits impulses between afferent and efferent neurons

Mechanoreceptors

Specialized structures that respond to mechanical forces (touch and pressure) within tissues and then transmits signals through sensory nerves

Somatic Nervous System

Nerves that serve the outer areas of the body and skeletal muscle and are largely responsible for the voluntary control of movement

Autonomic Nervous System (ANS)

A division of the peripheral nervous system that supplies neural input to organs that run the involuntary processes of the body (e.g., circulating blood, digesting food, producing hormones)

Sympathetic Nervous System

Subdivision of the autonomic nervous system that works to increase neural activity and put the body in a heightened state

Parasympathetic Nervous System

Subdivision of the autonomic nervous system that works to decrease neural activity and put the body in a more relaxed state

Sensory Function

Ability of the nervous system to sense changes in either the internal or external environment

Proprioception

The body's ability to naturally sense its general orientation and relative position of its parts

Integrative Function

The ability of the nervous system to analyze and interpret the sensory information to allow for proper decision-making, which produces an appropriate response

Motor Function

The neuromuscular (or nervous and muscular systems) response to the integrated sensory information

Muscle Spindles

Sensory receptors sensitive to change in length of the muscle and the rate of that change

Stretch Reflex

Neurological signal from the muscle spindle that causes a muscle to contract to prevent excessive lengthening

Sensory, Integrative, and Motor Function

Golgi Tendon Organ (GTO)

A specialized sensory receptor located at the point where skeletal muscle fibers insert into the tendons of skeletal muscle; sensitive to changes in muscular tension and rate of tension change

Joint Receptors

Receptors located in and around the joint capsule that respond to pressure, acceleration, and deceleration of the joint

Neuroplasticity

The concept that the brain will continually change or grow, reforming neural pathways throughout an individual's entire life span

Neurocircuitry

The interconnection of neurons in the brain and spinal cord

Motor Skills

Specific movements through the coordinated effort of the sensory and motor subsystems

Motor Skills Development Process

Stage 1 (cognitive): The client is just learning a skill. They understand the goals of the skill and develop movement strategies and can perform the skill but with inconsistent performance.

Stage 2 (associative): The client begins to understand the skill. Through practice, they refine the skill and movement strategy and can perform the skill with less error.

Stage 3 (autonomous): The client has mastered the skill. They perform the skill consistently with no error and independently modify the skill without error.

Skeletal System

A description of the bones of the body

Osteoporosis

A condition of reduced bone mineral density, which increases risk of bone fracture

Joints

The sites where two bones meet and movement occurs as a result of muscle contraction

Axial Skeleton

A division of the skeletal system consisting of the skull, the rib cage, and the vertebral column

Appendicular Skeleton

A division of the skeletal system consisting of the arms, legs, and pelvic girdle

Levers

Rigid rods where muscles attach

Remodeling

The process by which bone is constantly renewed by the resorption and formation of the bone structure

Osteoclasts

Special cells that break down and remote old bone tissue

Osteoblasts

Special cells that form and lay down new bone tissue

Wolff's Law

Scientific explanation of how remodeling (new bone growth) occurs along the lines of stress placed on the bone

Long Bones

Characterized by the their long cylindrical body, with irregular or widened bony ends. They are shaped much like a beam and exhibit a slight curvature that is necessary for efficient force distribution. Long bones are composed predominantly of compact bone tissue to ensure strength and stiffness. However, they do have a considerable amounts of spongy bone tissue for shock absorption.

Short Bones

Similar in length and width and appear somewhat cubical in shape. They consist predominantly of spongy bone tissue to maximize shock absorption. The carpals of the wrists and tarsals of the ankles fit this category for bones

Flat Bones

Flat bones are thin bones comprising two layers of compact bone tissue surrounding a layer of spongy bone tissue. These bones protect internal structures and provide broad attachment sites for muscles

Irregular Bones

Bones of unique shape and function that do not fit the characteristics of the other categories

Sesamoid Bones

Small bones embedded in a joint capsule or found in locations where a tendon passes over a joint. Found in the hands and feet. Sesamoid bones develop within particular tendons at a site of considerable friction or tension. They serve to improve leverage and protect the joint from damage

Processes

Projections protruding from the bone where tendons and ligaments can attach

Vertebral Column

Bones that house the spinal cord; consists of the cervical, thoracic, lumbosacral regions

Spinal Cord

Bundle of nerves housed within the vertebrae

The Spine

Segments of the Vertebral Column

Intervertebral Discs

Fibrous cartilage structures between vertebrae that act as shock absorbers and assist with movement

Neutral Spine

Represents a position in which the vertebrae and associated structures are under the least amount of load and can most optimally support functional movement

Osteokinematics

Movement of a limb that is visible

Arthrokinematics

The description of joint surface movement; consists of three major types: roll, slide, and spin

Synovial Joints

A joint with a fluid-filled joint capsule

Nonaxial Joints

A gliding joint that moves in only one plane, either back and forth or side to side

Nonsynovial Joints

Joints that have no joint capsule, fibrous connective tissue, or cartilage in the uniting structure

Ligament

A fibrous connective tissue that connects bone to bone

Collagen

A protein found in connective tissue, muscles, and skin that provides strength and structure. It is the most abundant protein in the human body

Elastin

A protein that provides elasticity to skin, tendons, ligaments, and other structures

Growth Plate

A specialized cartilage disc located in the epiphysis that is responsible for longitudinal bone growth

Skeletal Muscle

The type of muscle tissue that connects to bones and generates the forces that create movement

Fascia

Connective tissue that surrounds muscles and bones

Epimysium

Inner layer of fascia that directly surrounds an entire muscle, commonly referred to as the "deep fascia"

Fascicles

Largest bundles of fibers within a muscle. Fascicles are surrounded by perimysium

Perimysium

Connective tissue surrounding a muscle fascicle

Endomysium

Connective tissue that wraps around individual muscle fibers within a fascicle

Tendon

connects muscle to bones

Ligaments

Connect bones to bones

Glycogen

Glucose that is deposited and stored in bodily tissues, such as the liver and muscle cells; the storage form of carbohydrate

Myoglobin

Protein-based molecule that carries oxygen molecules into the muscles

Myofibrils

The contractile components of a muscle cell; the myofilaments (actin and myosin) are contained within a myofibril

Myofilaments

The filaments of a myofibril; include actin and myosin

Actin

The thin, stringlike, myofilament that acts along with myosin to produce muscular contraction

Myosin

The thick myofilament that acts along with actin to produce muscular contraction

Sarcomere

The structural unit of a myofibril composed of actin and myosin filaments between two Z-lines

Z-line

The meeting point of each sarcomere

Neural Activation

The nervous system's signal that tells a muscle to contract

Neuromuscular Junction

The specialized site where the nervous system communicates directly with muscle fibers

Synapse

A junction or small gap between the motor neuron and muscle cells

Motor Unit

A motor neuron and all of the muscle fibers that it innervates

Muscle Anatomy Flowchart

Muscle: bundle of fascicles surrounded by epimysium (deep fascia) connective tissue

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Fascicle: bundles of muscle fibers surrounded by perimysium connective tissue

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Muscle fiber: a bundle of myofibrils surrounded by endomysium connective tissue

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Myofibril: a collection of repeating sarcomeres that contain myofilaments (actin and myosin)

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Sarcomere: a section of a myofibril between two Z-lines where muscle contraction physically occurs

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Myofilament: the individual protein structures, actin and myosin, that make up a myofibril

Action Potential

Nerve impulse that is relayed from the central nervous system, through the peripheral nervous system, through the peripheral nervous system, and into the muscle across the neuromuscular junction

Neurotransmitters

Chemical messengers that cross the synapse between neuron and muscle and assist with nerve transmission

Acetylocholine (ACh)

A neurotransmitter that helps the action potential cross the synapse into the muscle, which initiates the steps in a muscle contraction

Sliding Filament Theory

The series of steps in muscle contraction involving how myosin (thick) and actin (thin) filaments slide past one another to produce a muscle contraction, shortening the entire length of the sarcomere

Excitation-contraction Coupling

The physiological process of converting an electrical stimulus to a muscle contraction

Power Stroke

The myosin heads bind to actin and pull them toward the sarcomere center, which slides the filaments past each other, shortening the muscle

Adenosine Triphosphate (ATP)

A high-energy molecule that serves as the main form of energy in the human body; known as the energy currency of the body

Resting Length

The length of a muscle when it is not actively contracting or being stretched

Type I Muscle Fibers

Muscle fibers that are small in size, generate lower amounts of force, and are more resistant to fatigue

Type II Muscle Fibers

Muscle fibers that are larger in size, generate higher amounts of force, and are faster to fatigue

All-or-nothing Principle

Motor units cannot vary the amount of force they generate; they either contract maximally or not at all

Type IIx Muscle Fibers

have lower oxidative capacity and fatique very quickly

Type IIa Muscle Fibers

also called intermediate fast-twitch fibers, higher oxidative capacity and fatigue more slowly than Type IIx but still fatigue much faster than Type I Fibers

Capillaries

the smallest blood vessels and the site of exchange of elements between the blood and the tissues

Characteristics of Type I Muscle Fibers

- more capillaries, mitochondria, and myoglobin

- increased oxygen delivery

- smaller in size

- less force produced

- slow to fatigue

- long-term contradictions (stabilization)

- "slow twitch"

Characteristics of Type II Muscle Fibers

- fewer capillaries, mitochondria, and myoglobin

- decreased oxygen delivery

- larger in size

-more force produced

- quick to fatigue

- short-term contractions (force and power)

- "fast twitch"