Exam 1 Study Guide Flashcards
Study of human movement
Kinesiology’
Application of mechanical principles in the study of living organisms
Biomechanics
Branch of mechanics dealing with systems in a CONSTANT state of motion
Statics
Branch of mechanics dealing with systems subject to ACCELERATION
Dynamics
Study of the action of forces
Kinetics
Study of the description of motion, including considerations of space and time
Kinematics
Involving non- numeric description of quality
Qualitative
Involving the use of numbers
Quantitative
Motion along a line, either straight or curved
Linear motion
Another term for linear motion
Translation
Motion along a straight line
Rectilinear motion
Motion along a curved line
Curvilinear motion
A long jumper in mid air follows what path?
Curvilinear
Rotation around a central imaginary line
Axis of rotation
Rotation of a body segment around a joint is an example of what?
Angular motion
Combination of linear and angular motion
General motion
What motion is most involved in human movement?
General motion
A body or portion of a body that is chosen for analysis
Mechanical system
Erect standing position with all body parts facing forward, serves as starting point for defining movement terms
Anatomical Reference Position
Direction: Closer/Further to the head
Superior/Inferior
Direction: Toward the front/back
Anterior(ventral)/Posterior(dorsal)
Direction: Toward/Away from the midline
Medial/Lateral
Direction: Closer/Further from the trunk
Proximal/Distal
Direction: Toward/Away from the surface
Superficial/Deep
Divides the body into left and right halves
Sagittal plane
Divides the body into front and back halves
Frontal plane
Divides the body into top and bottom halves
Transverse planes
Movements within Sagittal plane (4)
Flexion
Extension
Dorsiflexion (upward)
Plantar flexion (downward)
Movements within Frontal plane (2)
Abduction
Adduction
Movements within Transverse plane (3)
External/Internal rotation
Pronation
Supination
Axis perpendicular to the Sagittal plane allowing flexion/extension
Mediolateral/Frontal Axis
Axis perpendicular to the frontal plane, allowing abduction,adduction
Anteroposterior Axis
Perpendicular to the transverse plane allowing rotation
Longitudinal axis
A system used to standardize quantitative descriptions of human motion
Spatial Reference Systems
Most commonly used Spatial Reference system
Cartesian Coordinate System (2D and 3D measurements)
CS: Used for linear movements (ex: running ,cycling, jumping)
2D Analysis
CS: Uses cameras track joint markers for a more detailed assessment
3D Analysis
CS: Identifies movement directions
Positive & Negative coordinates
Visual representation of an individual’s motion using dots of LIGHT at major joints
Point Light Display
TF: PLD helps researchers study kinetics without distraction from body shape
False
Kinematics
Visual observation method used to analyze human motion
Qualitative Analysis
Prerequisite knowledge for Analysis (2)
Understanding the Skill
Gaining Biomechanical Knowledge
The tendency of an object to resist changes in its state of motion; proportional to mass
Inertia
The quantity of matter composing a body; measured in kilograms (kg)
Mass (m)
A push or pull acting on an object; X = ma (measured in Newtons, N)
Force (F)
The overall force acting on a system after all forces are accounted
for
Net force
The force of gravity acting on an object; X= m × ag (ag = -9.81
m/s² on Earth)
Weight (wt)
The point where weight is equally distributed in all directions
Center of gravity
Force per unit area (N/m² or Pascals, Pa)
Pressure (P)
The amount of three-dimensional space occupied by a body (m³, L)
Volume (V)
Mass per unit volume (kg/m³)
Density (ρ)
The rotational effect of a force; X = F × d (Newton-meters, Nm)
Torque (T)
A change in momentum over time; X = F × t (Ns)
Impulse (J)
Visual representation of all forces acting on an object
Free Body Diagram
Greater torque = __ rotational motion
More
Applying force over time (J), changes an object’s __
Momentum
Mechanical Loads: The effect of a force depends on its (DDDM)
Distribution
Direction
Duration
Magnitude
TF: If Net Force ≠ 0, motion occurs in the opposite direction of the net force
False
In the direction of
Load: Pulling or stretching force directed axially
Tension
Load: Pressing or squeezing force directed axially
Compression
Visual representation of an individual’s motion using dots of LIGHT at major joints
Point Light Display
Load: Force directed parallel to a surface
Shear
Load: Asymmetric loading creating tension on one side and compression on the other
Bending
Load: The simultaneous action of more than one type of loading
Combined loading
Load most common in the body
Combined loading
Force per unit of area over which force acts (N/m² or N/cm²)
Stress
Change in shape due to applied force
Deformation
Load Deformation Curve: Temporary deformation; returns to original shape
Elastic Region
Load Deformation Curve: Permanent deformation
Plastic Region
Load Deformation Curve: Stuctural Integrity is lost (bone fracture, tissue rupture)
Failure Point
(Microtrauma): Low-magnitude, repeated applications
(ex. running injuries)
Repetitive loading
(Macrotrauma): Single high-magnitude application causing
injury (ex. bone fracture from a fall)
Acute loading
Quantities with only magnitude (ex. mass, volume, length, speed)
Scalars
Quantities with magnitude and direction (ex. force, velocity,
acceleration, displacement)
Vectors
Determining a single vector from two or more vectors
by vector addition
Vector composition
Graphical method where the tip of one vector connects
to the tail of the next
Tip-to-tail method
Breaking down a single vector into two perpendicular
components
Vector resolution
The extent to which an object resists deformation in response to an applied force
Stiffness (bone)
The amount of loading an object can withstand before failure
Strength(bone)
Ability to resist compression OR the maximum load that a material can withstand before permanently deforming or breaking
Compressive strength
Ability to resist tension
Tensile strength
Pressing or squeezing force directed axially through a body
Compressive stress
Force directed parallel to a surface
Shear stress
Characteristic of exhibiting different strength and
stiffness depending on the direction of the incoming load
Anisotropic characteristic
Cortical bone is strongest in resisting __ stress
Compressive
Cortical bone is weakest in resisting __ stress
Shear
Skeleton: Skull, Vertebra, Sternum, and Ribs
Axial skeleton
Skeleton: Bones composing the body appendages (limbs)
Appendicular skeleton
Specialized cells that BUILD bone tissue
Osteoblasts
Specialized cells that RESORB bone tissue
Osteoclasts
Increase in bone mass
Bone hypertrophy
Decrease in bone mass
Bone atrophy
Mechanical functions of Bone in human beings (2)
-Provides a rigid skeletal framework
-Provides protection to other body tissues
TF: Water content of bone (25-30%) affects bone stiffness
False
Strength
Amount of bone volume filled with pores or cavities
Bone porosity
TF: Bone porosity affects bone strength
True
Compact mineralized bone (Low Porosity)
Cortical bone
Less compact mineralized
connective tissue (High Porosity)
Trabecular (cancellous) bone
TF: Bones have the characteristics of Stiffness and Strength
True
Location of Cortical bone AND Trabecular bone
C: Shafts of long bones
T: Ends of long bones and vertebrae
Molecules that contribute to stiffness and compressive strength in bone (2)
Calcium Carbonate
Calcium Phosphate
A protein that provides flexibility and tensile strength to the bone
Collagen
TF: Collagen is lost with aging, leading to increase in bone brittleness
True
Cortical bone is __ than Trabecular bone
Stiffer
Trabecular bone is __ than cortical bone
Spongier
TF: Cortical bones can withstand more stress but less strain/ deformation
True
TF: Trabecular bone can undergo more strain/deformation before fracturing
True
Small cube-shaped bones that provide limited gliding and shock absorption
Short bones
Large flat bones that provide protection to body tissues and
large surface for attachments of muscles and ligaments
Flat bones
Bones with irregular (specific for their role) shapes to
fulfill their required functions in the human body
Irregular bones
Bones with a long cylindrical shaft (cortical bone) with bulbous
ends classified as condyles, tubercules, or tuberosities that make up the
framework of the APPENDICULAR skeleton.
Long bones
The inner layer of the __ builds CONCENTRIC layers of new bone tissue on top of existing layers
Periosteum
New bone cell production occurs at growth centers known as __, until it closes during late adolescence or early adulthood
Epiphyses
The DENSITY of bones are a function of the MAGNITUDE and DIRECTION of the mechanical stresses that are acting on the bone.
Wolff’s Law
As mechanical stress increases, so does osteoblast activity
Positive correlation
As mechanical stress decrease, so does osteoclast activity
Negative correlation
The ONLY tissue capable of actively developing tension
Muscle tissue
Muscle tissue requires stimulation by the __ system
Neuromuscular
Ability to be stretched or to increase in length
Extensibility
Property of muscle that allows progressive increases in
length over time when stretched.
Viscoelasticity
TF: Muscle will immediately recoil to resting length
False
Will not but gradually over time
Ability to return to normal resting length, following a stretch
Elasticity
Passive elastic property of muscle
provided by the MUSCLE MEMBRANES
Parallel Elastic Component (PEC)
Passive elastic property of muscle
residing in the TENDONS
Series Elastic Component SEC
The primary component of the elasticity of the human skeletal muscle
SEC
Ability to respond to a stimulus (stimulate to irritate)
Irritability
The contractile component (myosin & actin crossbridge) provides the ability to develop tension in the muscle.
Ability to develop tension
Singular muscle cell that is specialized to contract and generate tension
Muscle fiber
Muscle fiber is surrounded by __ membrane
Sarcolemma
Sarcolemma contains a specialized cytoplasm called…
Sarcoplasm
Hypertrophy may occur as increased increases in __ and/or __
Length, diameter
Fiber __ may be increased via resistance training
diameter
A single motor neuron and all the muscle fiber it innervates
Motor unit
The functional unit of the neuromuscular system
Motor unit
Most are composed of __-type cells whose response is developing tension in a twitch like fashion to a single stimulus.
Twitch
If an impulse is strong enough to release a sufficient amount of neurotransmitters, all the fibers innervated by that motor neuron will
contract
All-or-None Principle
AoN: If another action potential reaches the muscle fibers before relaxation,
the muscle fibers will contract harder
Temporal summation or increased firing rate/frequency
Motor units are recruited in an orderly process from smallest to largest
Size Principle
Force output is changed by either:
Increasing the firing frequency
Activating more motor units
Which twitch fiber reaches peak tension relatively quickly?
Fast twitch
Which twitch fiber reaches peak tension relatively slower?
Slow twitch
Which twitch fiber is the first to be recruited?
Slow twitch, type 1
Fibers are roughly parallel to the longitudinal axis
of the muscle.
Parallel Fiber Arrangement
Fibers lie at an angle to the muscle’s longitudinal
axis
Pennate Fiber Arrangement
Which fibers attach to one or more tendons?
Pennate fibers
Angle that increases as tension increases in the muscle fibers
Angle of pennation
Shortening of a muscle
Concentric
Lengthening of a muscle
Eccentric
No change in muscle length
Isometric
Acts to slow or stop a movement
Antagonist
Acts to stabilize a body part against some other force
Stabilizer
Acts to eliminate an unwanted action produced by an agonist
Neutralizer
Magnitude of the force generated by muscles is related to: (V,l)
-Velocity of muscle shortening
-Length of muscle when stimulated
Two-joint muscles can’t stretch enough to allow full
range of motion at both joints simultaneously
Passive insufficiency
Two-joint muscle can’t SHORTEN enough to cause full range of motion at both crossed joints
Active insufficiency
Force-Velocity Curve: Eccentrically, force and velocity have a __ relationship
Proportional
Force-Velocity curve: Concentrically, Force and Velocity have an __ relationship
Inverse
Force-Velocity curve: Isometrically, Force and Velocity have __ relationship
No, V = 0
Which contraction can produce the greatest force?
Eccentric
LTR: The total net tension present in a stretched muscle is the sum of (2)
Active tension
Passive tension
Length Tension Relationship: Force generation is at its peak when the muscle is slightly _
Stretched/Lengthened
Eccentric contraction followed immediately by the concentric contraction
Stretch-Shortening Cycle
Measures electrical activity produced by the muscle (myoelectric activity) with the use of transducers (electrodes)
Electromyography (EMG)
EMG: Applied at the surface of the skin to record myoelectric activity of muscle closer to the surface
Surface electrode
Inserted into muscular tissue to record myoelectric activity of deep muscle fibers
Indwelling (fine wire) electrodes
Time between the arrival of neural stimulus
and tension development by the muscle (Time from stimulation to action)
Electromechanical Delay
The amount of maximum torque an entire muscle group can generate at a joint
Muscular strength
TF: In muscular strength, if muscle force is parallel to the bone, torque will be produced
False
Rate of torque production at a joint
Muscular power
Muscular power is affected by (2)
Muscular strength
Movement speed
Ability of a muscle to exert tension over time or repeatedly
Muscular endurance
Reduced capacity of muscle fibers to produce force
Muscle fatigue
Load: Producing twisting around the longitudinal axis
Torsion
TF: PLD helps researchers study kinetics without distraction from body shape
False
Kinematics
WL: Weight bearing Exercise promotes _ _ due to proportional response or osteoblast activity
Bone development
WL: Mechanical stress has a __ correlation w/ osteoblast activity and __ correlation w/ osteoclast activity
Positive
Negative
TF: Increasing temperature will decrease the speed of nerve and muscle function
False
Increase
Tension provided by the MUSCLE FIBERS (contraction)
Active tension
Tension provided by the TENDONS and the MUSCLE MEMBRANES (PEC & SEC)
Passive tension
The elasticity of human skeletal muscle tissue is believed to be due primary to…(Acronym)
Series elastic component (SEC)
