MOTION ANALYSIS
BY
DR. AJAY KUMAR
READER
SCHOOL OF PHYSICAL EDU.
KINESIOLOGICAL ANALYSIS
A kinesiological analysis of a motor
skill consist of breaking the skill into
its constituent elements, of
determining the nature of each
movement and identifying the
appropriate mechanical and
anatomical principles.
POINTS TO BE KEPT IN MIND
What joints are involved
What are their exact movement in motion
Are any joint used their full range
What muscles are responsible for joint
action
What are the nature of contraction of each
muscle
Do any of the muscle group exert maximal
or near maximal effort
POINTS TO BE KEPT IN MIND
(cont)
What anatomical and mechanical
principles contribute for maximal
efficiency and accuracy (their
identification, their faults and their
correction)
What principles are directly related
to avoidance of injuries
Mechanical Analysis
The mechanical analysis of an
activity involves the identification of
laws and principles which help to
explain the most appropriate form
for the execution of the activity and
to identify the mechanical reason for
success or failure.
Biomechanical Analysis
Biomechanical analysis is the process
of identifying both the internal as
well as external forces coming into
play during the performance and the
effect produced by these forces on
that performance.
WHY MAKE ANALYSIS
As an aid to effective teaching
Provide instructor a sound
background for presenting a motor
skill
It provide instructor an X-Ray eye to
diagnose fault and difficulty
It make instructor more aware of
types on injuries which may occur
Methods of Analysis
Qualitative Analysis
Quantitative Analysis
Methods of Analysis
Qualitative Analysis : The performance is
evaluated subjectively on the basis of
direct visual observation.
Quantitative Analysis : The performance is
first recorded using photography,
cinematography, electromyography or
some other technique and then evaluated
objectively on the basis of measurements.
Characteristics of Qualitative
Analysis
Used by Phy Edu. Teachers, coaches,
athletes, spectators etc.
Based on a simple Visual observation of
the result.
It is a systematic evaluation not only
results but also all the various factors
which have contributed.
Use of Video Feedback method is now a
days more popular .
It is subjective in nature
Characteristics of Quantitative
Analysis
Used extensively by researchers
occasionally by coaches and rarely
by physical edu. Teachers.
Used for searching new techniques
Used for searching new equipments
Used for enhancing the performance
Expensive equipments are required
Highly trained people are required
Characteristics of Quantitative
Analysis (Cont)
More time are required for this type
of analysis
Generally conducted at the highest
level of competition
It is basically objective in nature
Basic Steps in Qualitative Analysis
Step 1 : Development of a model (or
block diagram) showing the
relationship between the results and
the factors that produce that results
RESULTS
FACTORS
WHICH PRODUCES
RESULTS
Basic Steps in Qualitative Analysis
(cont)
Step 2 : Observation of the
performance and identification of
faults.
Step 3 : Evaluation of the relative
importance of these faults
Step 4 : Instructions to the
performer in accord with the
conclusion reached in the course of
the analysis
STEPS OF ANALYSIS
Name of the skill
Brief description of the skill
The specific objective of the motor
skill
Identification of major and secondary
categories
STEPS OF ANALYSIS (cont)
The objectives of analysis i.e.
mechanical, anatomical or both
Identification of principles
Application of principles in motor
skills
Analysis of Walking
Name of the skill:
Walking
Description of Skill
Walking is a reflex action.
No conscious control is required.
If attention is focused on any part of
the gait tension is likely to develop
and rhythem is lost
Walking is performed by alternating
action of two lower extremities.
Description of Skill (cont)
It is an example of translatory
motion of the body as a whole which
is brought about by means of the
angular motion of some of its part.
It is also an example of a periodic or
pendular like motion in which the
moving segment may be said to start
at zero, pass through its arc of
motion and fall to zero again.
Description of Skill (cont)
In walking each lower extremities
undergoes two phase; the swinging
phase and the supporting phase.
The supporting phase is further
divided into a restraining phase
(from the moment the foot touches
the ground until it is directly under
the center of the body)
Description of Skill (cont)
The next phase of supporting phase
is propulsion phase (from the
moment when the foot is under the
center of gravity until it leaves the
ground).
Objective of Motor Skill
To produce a efficient linear motion
of the body as a whole by using
proper functioning of the reflexes ,
normal flexibility of the joints and
optimum use of the muscular force
and optimum stability of the body as
a whole in the weight bearing phase
of the motion.
Identification of Categories
Primary Category: Giving impetus to
one’s own body.
Secondary Category: Supported by
ground and locomotion on foot.
Objective of Analysis
Mechanical Analysis
Identification of Principles
Both part of law of inertia
Law of action and reaction
Law of lever
Newton’s second law
Law of stability
Law of Friction
Application of Mechanical
Principles
Principle 1: A body at rest will
remain at rest unless acted upon by
a force. Since walking is produces by
a pendular like motion of the lower
extremities the inertia of the body
must be overcome at every step.
Application of Mechanical
Principles (cont)
Principle 2: A body in motion will
continue in motion unless acted upon
by a force. Since motion is imparted
to the trunk by the backward thrust
of the leg, the trunk has a tendency
to continue moving forward even
beyond the base of support. A brief
restraining action of the forward leg
serve as a check on the momentum
of the trunk.
Application of Mechanical
Principles (cont)
Principle 3: Force applied diagonally
consist of two components ,
horizontal and vertical. The vertical
component in walking serves to
counteract the downward pull of the
gravity. The horizontal component
serves (1) in the restraining phase to
check the forward motion and (2) in
the propulsion phase to produce it.
Principles (cont)
Principle 4 : Translatory motion of
a lever is achieved by the repeated
alternate motion of two rotatory
motion. The lever turning first about
one end and then the other end. In
walking, the lower extremity
alternates between rotating about
the foot point of contact with the
ground and the hip joint.
Principles (cont)
Principle 5: the speed of the gait is
directly related to the magnitude of
the pushing force to the direction of
its application. This force is provided
by the extensor muscles of the hip,
knee and ankle joint, and the
direction of application is determined
by the slant of the lower extremity
when the force is being applied.
Principles (cont)
Principle 6: The economy of the
gait is related to its timing with
reference to the length of the limbs.
The most economical gait is one
which is so timed as to permit
pendular motion of the lower
extremities.
Principles (cont)
Principle 7 : Walking has been
described as an alternating loss and
recovery of balance. This indicates
that a new base of support must be
established at every step.
Principles (cont)
Principle 8 : As propulsion of the
body is brought about by the
diagonal push of the foot against the
supporting surface, the efficiency of
the locomotion depends on the
counter pressure and friction
provided by the supporting surface.
Principles (cont)
Principle 9 : Stability of the body is
directly related to the size of base of
support. In walking the lateral distance
between the feet is a factor in maintaining
balance.
– Too narrow a lateral distance between the feet
decrease the balance
– Too wide a lateral distance between the feet
increase stability but cause the body sway side
to side
– The optimum position of the feet appears
perfect when the inner borders of foot falls
along a single straight line