REC 3010
HUMAN MOVEMENT
THE STRUCTURE OF MUSCLE
CONNECTIVE TISSUE/FASCICLES
AGONIST AND ANTAGONIST MUSCLES
Agonist-Antagonist Muscles
Upper Trapezius
Levator Scapulae
Middle Trapezius
Rhomboid Minor
Serratus Anterior
Rhomboid Major
Lower Trapezius
The Upper Trapezius and the Lower Trapezius have an
Agonist-Antagonist relationship
Agonist-Antagonist Muscles
Glenohumeral
joint
Greater
Tubercle
Lesser Tubercle
Subscapularis
Supraspinatus
Infraspinatus
Teres Minor
The Subscapularis and the Supraspinatus/Infraspinatus/Teres
Minor have a Agonist Antagonist relationship
The muscles of the Abdominals are opposite the Lower Back
External
Abdominal
Oblique
Pectoralis Major
Rectus Abdominal
Internal
Abdominal
Oblique
Transverse Abdominis
Tendinous
Transcriptions
Longissimus
Spinalis
Iliocostalis
The Transverse
Abdominals are opposite
each other
There are some interesting Agonist Antagonist relations between
the Hip Extensors and the Hip Flexors
Semimembranosus
Semitendonosus
Biceps
Femorus
Vastus
Lateralis
Vastus
Medialis
Vastus
Intermedialis
Vastus
Lateralis
AGONIST/ANTAGONIST STRENGTH RATIOS
ACTIN & MYOSIN FILAMENTS
(SLIDING FILAMENT THEORY)
ACTIN & MYOSIN FILAMENTS
SARCOMERE DIAGRAM
MYOSIN CROSS BRIDGE IN ACTION
MUSCLE CONTRACTION/RELAXATION
NEUROMUSCULAR JUNCTION
PRODUCING A MUSCLE ACTION
ISOTONIC CONTRACTION
*CONCENTRIC CONTRACTION
-muscle acts as moving force
-muscle shortens creating tension
-motion is created
*ECCENTRIC CONTRACTION
-muscle acts as a resistive force
-external force exceeds contractive force
-muscle lengthens & motion is slowed
ISOMETRIC CONTRACTION
-
-muscle tension is created with no movement
-resistance comes from opposing muscle,
gravity or an immoveable object
-motion is prevented by equal opposing forces
WHICH MUSCLES ACT AS
• There are three
lever classes.
• The body operates
primarily as a series
of third-class levers,
with only a few
first- and secondclass levers.
– Force (F) acts
between the axis
(X) and the
resistance (R)
ST
1
&
ND
2 ?
LEVERS OF THE BODY
1ST CLASS LEVER
2ND CLASS LEVER
3RD CLASS LEVER
ST
1
CLASS LEVER
ND
2
THE WEIGHT OF THE
BODY PROVIDES THE
REISISTANCE LOAD
CLASS LEVER
WHEN THE CALF
CONTRACTS IT
PROVIDES THE EFFORT
FORCE
THE FOOT ACTS AS
THE RESISTANCE
ARM
THE BALL OF FOOT
ACTS AS FULCRUM OR
AXIS OF ROTATION
7 Principles of Biomechanics
Principle #1: Stability
The lower the center of mass
the larger the base of support
the closer the center of mass to the base of support
& the greater the mass
The more stability increases
Example: Sumo Wrestler
Principle #2: Maximum Effort
The production of maximum force requires the use of all
possible joint movements that contribute to the tasks
objective
Example: Bench Press or Golf
Principle #3: Maximum Velocity
The production of maximum velocity requires the use of
joints in order from largest to smallest
Example: Slap Shot or Golf Drive
Principle #4: Linear Motion
The greater the applied impulse the greater the increase in
velocity
Example: Slam Dunking in Basketball
Principle #5: Linear Motion
Movement usually occurs in the direction opposite of the
applied force
Example: High Jumper, Runners & Cyclists
Principle #6: Angular Motion
Angular motion is produced by the application of a force
acting at some distance from the axis, that is, by torque
The production of Angular Motion
Example: Baseball Pitcher
Principle #7: Angular Momentum
Angular Momentum is constant when an athlete or object is
free in the air. Once an athlete is airborne, he or she will
travel with a constant angular momentum.
Example: Divers
Anatomical, Directional, and Regional Terms
Movement of the Skeleton
• There are three main types of joints:
– Fibrous joints
– Cartilaginous joints
– Synovial joints
• Synovial joint movement occurs within the three
planes of motion: sagittal, frontal, and transverse.
– Movement occurs along the joint’s axis of rotation, where
the plane of movement is generally perpendicular to the
axis.
– Uniplanar joints (hinge joints) allow movement in only one
plane.
– Biplanar joints allow movement in two planes that are
perpendicular to each other.
– Multiplanar joints allow movement in all three planes.
Movement in the Sagittal Plane
 The sagittal plane runs anterior-posterior, dividing the body into left and
right sections.
 Movements that involve rotation about a mediolateral axis occur in the
sagittal plane. Examples include:
–
–
–
–
Flexion
Extension
Dorsiflexion
Plantarflexion
Movement in the Frontal Plane
•
•
The frontal plane runs laterally, dividing the body into anterior and posterior
sections.
Movements that involve rotation about an anteroposterior axis occur in the frontal
plane. Examples include:
–
–
–
–
–
–
Abduction
Adduction
Elevation
Depression
Inversion
Eversion
Movement in the Transverse Plane


The transverse plane runs horizontally, dividing the body into superior and inferior
sections.
Movements that involve rotation about a longitudinal axis occur in the transverse
plane. Examples include:
–
–
–
–
–
Rotation
Pronation
Supination
Horizontal flexion
Horizontal extension
Movement of Synovial Joints
Angular Movements
*Flexion
*Extension
*Abduction
*Adduction
Circular Movements
*Circumduction
*Rotation
Movements Special to the Shoulder
*Protraction
*Retraction
*Elevation
*Depression
Movements Special to the Ankle
*Inversion
*Eversion
*Dorsiflexion
*Planterflexion
Anatomical Position