Exam 1 Study Guide Flashcards
Which type of contraction is the OPPOSITE of the action of a muscle?
Eccentric
What are the two arrangements of muscle?
Fusiform and pennate
What joints have 3 DOF?
Hip and Shoulder
What is unfused tetanus?
Generates series of summated mechanical twitches with no rest in between firing of action potentials
Where is the center of mass in women?
Below the belly button, closer to the hips
What is a synergist?
A muscle that assists a prime mover
What is the AOR for the sagittal plane?
Medial-lateral
What is a force couple?
Two forces acting in opposite linear directions to rotate a part around an axis producing the same rotary direction
What motions does a hinge joint allow?
Flexion and extension
What happens in a joint when water is increased?
Swelling, which is protection
What are the three tissues surrounding a joint?
Fibrous layer, tendons, ligaments
Why is ground substance important in articular cartilage?
Provides an ideal surface for distribution of constant repetitive forces
Where is the AOR in a 3rd class lever?
End of a bone
What does the epimysium do?
Forms the muscle
What is an example of an agonist?
Biceps in a bicep curl
What is an agonist?
Muscle Responsible for an action
What is an example of a synarthosis joint?
Skull sutures
Explain a Type II muscle fiber
Fast twitch, for short and powerful bursts
What is linear acceleration directly proportional to?
The force causing it and the acceleration acts in the same direction
What is an example of a force couple?
Trapezius and Serratus Anterior during upward rotation of scapula with arm elevation
What does the perimysium do in muscles?
Forms a channel for the blood vessels
What is an example of an antagonist?
Triceps in a bicep curl
What is a saddle joint?
Convex in one direction, concave in the other
What do muscles in parallel allow for?
Hypertrophy and increased contractile force
What is ground substance?
Gelatinous fluid that allows for water and nutrients to diffuse through cartilage
What is the max number of DOF at a joint?
3
Where is irregular dense connective tissue found?
Fibrous layer
Which is easier to lift: an object held at 90 deg. elbow flexion or an object being held at full elbow extension?
Object held at 90 deg elbow flexion
What is an example of a pivot joint?
Radius and ulna
When is angular force greatest?
When line of pull is perpendicular to bone
What is passive tension?
Stretching of a muscle. Muscle must reach critical length to generate tension
Where is the AOR in a 1st class lever?
Between two opposing forces
What are the two types of muscle fiber arrangement?
Pennate and fusiform
What is an antagonist?
A muscle having an opposite action of an agonist
What is an example of a concentric contraction in the quadriceps?
Quads in wall-sit going down to “sitting” position
What movements are allowed in the frontal plane?
Lateral Flexion, Abduction/Adduction, Elevation/Depression, Upward/Downward Rotation, Inversion/Eversion, Deviations
What is translation?
An object moving linearly (wheelchair)
What is an example of a synergist?
Brachioradialis in a bicep curl
What are osteokinematcs?
Motion of bones
What happens when the mass moment of inertia is lower?
More torque
What is the average AOR of a bone?
Anatomical landmark through the convex surface
What is mass moment of inertia?
Body’s resistance to change in rotation or angular momentum
In kinetics, force is directly _________ to acceleration
Proportional
What are kinetics?
Effect that forces have on the body
What is a diarthrosis joint?
Articulation between two bones
What is Wolff’s Law?
Bone responds to stress by producing more bone
In concave on convex movements, where does the moving segment roll and slide?
Rolls and slides in same direction
What shape is the rectus femoris muscle?
Pennate
What does a condyloid joint allow?
Biplanar movement
What is an example of a first class lever?
Neck moving anteriorly/posteriorly
Explain a Type I muscle fiber
Slow twitch, used for endurance
What are three examples of Type II muscle fibers?
Biceps, Triceps, Quads
What does regular dense connective tissue provide and restrain?
Provides tension and restrains undesirable motion in single parallel directions
What is the actual line of pull determined by?
Morphology and joint angle
What are two examples of ball and socket joints?
Hip, shoulder
In convex on concave movements, where does the moving segment roll and slide?
Rolls in one direction, slides in opposite
How is force produced in terms of rate coding?
Produced by the muscle fibers is strongly modulated by the discharge rate of sequential action potentials
What is torque?
Force multiplied by its moment arm and tends to rotate a body or segment around an AOR
What is rotation?
Angular motion that causes rotation (rocking chair)
What is an example of an eccentric contraction in the quadriceps?
Quads in a wall-sit going back up
What is the interspike interval?
Average discharge rate of an action potential in frequency
What are arthrokinematics?
Motion of joints
What is the force velocity relationship?
Speed of task being completed and the force produced
What is a concentric contraction?
A contraction in which the muscle shortens
How is force and velocity related in a max effort eccentric contraction?
Force is directly proportional to velocity
What are the three structural elements of a muscle?
Epimysium, Perimysium, Endomysium
What does irregular dense connective tissue resist?
Tensile forces in multiple directions
What does a pivot joint do?
Spins around a single AOR
Which type of bone is thicker?
Compact bone
What are the two ways to increase torque?
Increase the size of the force and increase the length of the moment arm
What does a plane joint allow?
Translation or translation + rotation
What is the AOR of the frontal plane?
Anterior-posterior
What is the optimal length for optimal force production?
90 degrees
What is an example of a isometric contraction in the quadriceps?
Quads in a wallsit
What type of bone covers the ends of long bone?
Cancellous bone
What are the two types of recruitment?
Spatial and Temporal
What happens in a cross bridge?
Force is generated
What is active tension?
Active tension is generated by a stimulus when actin and myosin slide past each other
What is muscle morphology?
The way fibers are arranged
Why does bone produce more bone?
Rich blood supply
What are examples of a hinge joint?
Elbow, knee
What is an ovoid joint?
One convex surface, one concave surface
What is a synarthosis joint?
Junction between two bones with slight to no movement
What is an example of a condyloid joint?
Interphalangeal joints
How is force and velocity related in a max effort concentric contraction?
Force is inversely proportional to velocity
What does a saddle joint allow?
Biplanar movement
What is an eccentric contraction?
A contraction in which the muscle lengthens
What movements are allowed in the transverse plane?
Rotation, Internal/External Rotation, Protraction/Retraction, Pronation/Supination, Horizontal Abduction/Adduction
What is the force velocity curve?
Velocity of a muscle change in length and its maximal force ourput
What is torque?
A force that tends to rotate a body or segment
How can torque be modified?
Changing force or moment arm length
What is an isometric contraction?
A contraction in which the muscle length doesn’t change
Which type of contraction correlates with the action of a muscle?
Concentric
What is rate coding?
Process of when specific motor neurons is recruited
What is the AOR for the transverse plane?
Vertical
Which causes faster contractions: muscles in series or parallel?
Series
What does 2nd class levers favor?
Power
What three factors are involved in the mechanical alignment of muscles?
Moment arm of load, moment arm of muscles, orientation of forces
What do the elastic properties in regular dense connective tissue allow for?
Storage and release of energy while protecting against injury
What are the types of diarthrosis joints?
Hinge, Pivot, Ellipsoid, Ball and socket, plane, saddle, condyloid, ovoid
What is kinematics?
Description of motion, not forces
What is recruitment?
Initial activation of specific motor neurons that cause activation of associated muscle fibers
Explain the forces in a second class lever
Internal forces are greater than external forces
Do muscles pull or push?
Only pull
Where is the center of mass in men?
At or slightly above the belly button
What is an example of a saddle joint?
Thumb
What is an example of an ellipsoid joint?
Wrist bones
In first class levers, what direction does the internal and external forces go?
Same direction
What is a twitch?
Isolated contraction
What is an example of a 2nd class lever?
Gastrocnemius during a calf raise
What does a ball and socket joint allow?
Triplanar movement
What is temporal recruitment?
A mechanism that increases the strength of a muscle contraction by increasing the firing rate of active motor units
What 3 motions are used in arthrokinematics?
Roll, Slide, Spin
Explain the forces in a 3rd class lever.
External forces are greater than internal forces
What causes increased force through a muscle?
More cross bridges
How can a muscle have greater force?
Greater attachment angle
What joints spin?
Pronation, Glenohumeral Joint, Hip Joint
What are the two types of bone?
Compact and Cancellous
What is active force?
Force generated by a stimulus when actin slides past myosin and Z discs get pulled together in the sarcomere forming a cross bridge
What is an example of a plane joint?
Carpals
What are two examples of Type I muscle fibers?
Soleus and Erector Spinae
What shape is the biceps brachii muscle?
Fusiform
What does an ellipsoid joint allow?
Biplanar movement
What is angular acceleration directly proportional to?
The torque causing it and takes place in same direction
In closed chain concave on convex, which segment is fixed and which segment moves?
Proximal moves, Distal fixed
Where is the AOR in a second class lever?
End of a bone
In open chain concave on convex, which segment moves and which is fixed?
Proximal is fixed, Distal moves
What does 3rd class levers favor?
ROM
What is the maximum number of cross bridges determined by?
Muscles overall volume by length
What is spatial rectruitment?
Activation of more motor units to produce a greater force
What type of bone covers shafts of long bones?
Compact bone
What is fused tetanus?
Greatest force level that is possible for a single muscle fiber
What is the Length Tension Relationship of muscles involved?
Relationship between a muscle’s length and the tension it produces
What is an example of a 3rd class lever?
Bicep curl
What happens in the endomysium?
The location of metabolic change
What are the movements allowed in the sagittal plane?
Flexion, Extension, Hyperextension
