Download Biomechanics of Resistance Exercise

Biomechanics of Resistance
Exercise
Key Terms
Range of Motion
Movement Planes
Muscle Actions
Anatomical LocationsKey
Terms
• Midline: The invisible line that divides the body or a single body part in half down the center.
• Anterior: The surface of the body that would be considered the front.
o The pectorals are on the anterior aspect of the body
• Posterior: The surface of the body that would be considered the back.
o The rhomboids are on the posterior aspect of the body
• Superior: Toward the head or upper part of a structure:
o The humerus is superior to the radius
• Inferior: Toward the lower part of a structure
o The tibia is inferior to the femur
Anatomical LocationsKey
Terms
• Medial: The surface that is closer to the midline of the body.
o The adductors are medial to the abductors
• Lateral: The surface that is further from the midline of the body.
o The abductors are on the lateral aspect of the leg
• Proximal: Closer to the origin of a point of reference
o The elbow is proximal to the wrist
• Distal: Further from the origin or point of reference
o The foot is distal to the knee
Muscle MovementsKey
Terms
•  Agonist- (prime mover) the muscle most directly involved in bringing about a movement
•  Antagonist- the muscle that slows down or stops the movement. Opposes the agonist muscle
•  Synergist- Assists indirectly in a movement
•  Muscle origin (proximal attachment)- the point closest to the midline of the body where the
muscle attaches to the bone
•  Muscle insertion (distal attachment)- the point farthest from the midline of the body where the
muscle attaches to the bone
•  Stabilizer muscles- muscles acting in a stabilizing role that aren’t directly involved in lifting a
weight, but instead keep certain parts of the body steady so that the primary working muscles
can do their job properly.
•  Anatomical Position- The body is erect, the arms are down at the sides, and the palms face
forward.
Examples of Agonist vs.
Antagonist Muscles
Agonist (Prime Mover)
Antagonist
Biceps
Triceps
Deltoids
Latissimus Dorsi
Pectoralis Major
Trapezius/Rhomboids
Rectus Abdominis
Erector Spinae
Quadriceps
Hamstrings
Types of Muscular
Contractions
• Concentric Muscle Action- A muscle action in which the
muscle shortens because the contractile force is greater than
the resistive force.
• Eccentric Muscle Action- A muscle action in which the muscle
lengthens because the contractile force is less than the resistive
force.
• Isometric Muscle Action-A muscle action in which the muscle
length does not change because the contractile force is equal to
the resistive force.
The Three Movement Planes
•  Sagittal Plane: Divides the body into right and left parts.
o Primary movements include Flexion and Extension
•  Frontal Plane: Divides the body into anterior and posterior parts.
o Primary movements include Abduction, Adduction, and Lateral
Flexion
•  Transverse Plane: Divides the body into superior and inferior parts.
o Primary movements include Pronation, Supination, and any rotation
about a vertical axis.
Movement Planes
Anatomical Position
Anatomical Planes divide body or joint into 3 segments:
Sagittal
Frontal/Coronal
Transverse/Horizontal
Basic Description of
Movement
• Flexion : Decreasing the angle of a given joint.
• Extension : Returning a joint from flexion.
• Abduction : Movement away from the midline in the frontal plane.
• Adduction : Movement toward the midline in the frontal plane.
• Rotation : Movement counterclockwise or clockwise about a vertical
axis
• Pronation: Internal rotation resulting in appendage facing downward
• Supination: External rotation resulting in appendage facing upward
Examples of Planes and
Motions
Plane
Motion
Example
Sagittal
Flexion/Extension
Frontal
Abduction/adduction
Walking, squatting, overhead
press
Star Jump
Transverse
Side Flexion
Lateral Arm Raise
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