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Duration



4th week / 3 contact hrs.
5th week / 3 contact hrs.
topics





Types of muscle contraction (Isometric, Isotonic: Eccentric &
Concentric)
Role of muscles (agonist, antagonist, stabilizers, synergists,
neutralizers)
Muscle skeletal stabiliser generating an appropriate amount
of force at a given length
Muscle morphology: shape and structure
Muscle architecture
TYPES OF MUSCLE CONTRACTION
Concentric contraction
 Eccentric contraction
 Isotonic contraction
 Isokinetic contraction
 Isoinertial contraction
 Isometric contraction.

CONCENTRIC CONTRACTION

It is the type of muscle contraction in which the
muscle length shortens.
ECCENTRIC CONTRACTION
It is the type of muscle contraction in which the
muscle elongates.
ISOTONIC CONTRACTION

It is the type of muscle contraction in which the
muscle tone remains constant.
ISOKINETIC CONTRACTION
It is the type of muscle contraction in which the
angular velocity of the segment remains
constant.
 Variable resistance
 Possible with dynamometers.

ISOINERTIAL CONTRACTION

It is the type of muscle contraction in which the
resistance to the muscle remains constant.
ISOMETRIC CONTRACTION

It is the type of muscle contraction in which the
muscle length remains same.
FUNCTIONAL ROLE OF THE MUSCLES

Five different roles
 Agonist.
 Antagonist.
 Synergist.
 Fixators
or stabilizer.
 Neutralizers.
AGONIST

Muscle which acts as a primary mover of the
body segment.
 Example:
elbow flexion by brachialis.
ANTAGONIST

Muscle which act opposite to the agonist.
 Example:
contract
Relaxation of triceps when biceps
SYNERGIST
Muscle which assist the action of primary
mover or agonist.
 Contraction of rectus femoris during flexion of
hip joint by hip flexors.

STABILIZERS OR FIXATORS

Muscle which stabilizes the proximal segment
of the joint to be moved.
 Example:
stabilization of shoulder joint during
elbow flexion
NEUTRALIZERS

Prevents unwanted movement during the desired
movement.
Examples: the biceps can flex the elbow and supinate
the forearm. If only elbow flexion is wanted, the
supination component must be ruled out. Therefore,
the pronator teres, which pronates the forearm, would
contract to counteract the supination component of the
biceps, and only elbow flexion would occur.
 Neutralizers act to cancel out an unwanted movement

MUSCLE SKELETAL STABILISER GENERATING AN APPROPRIATE AMOUNT OF FORCE AT
A GIVEN LENGTH
Classification of muscle depending upon the
number of joints they cross.
1.
2.
3.
One joint muscle. Eg: Deltoid
Two joint muscle. Eg: rectus femoris
Multiple joint muscle. Eg: Flexor digitorum
MUSCLE INSUFFICIENCY WITH LENGTH
1.
2.
Passive insufficiency
Active insufficiency
ACTIVE INSUFFICIENCY
Insufficiency due to exhaustion of muscle to
contract further.
 Happens in multiple joint muscles.
 MUSCLE CANNOT COMPLETE THE ROM AS THE
MUSCLE HAS UNDERGONE FULL
CONTRACTION.
 EXAMPLE: ALL MULTI-JOINT MUSCLES.

PASSIVE INSUFFICIENCY
Insufficiency due to passive tension in the
opposite group of muscle.
 Happens in multiple joint muscles.
