This document discusses kinematic concepts for analyzing human motion. It defines anatomical reference position and provides directional terms to describe body positions. It also introduces reference planes and axes used to define types of motion like linear, angular and general motion. Specific motions in the sagittal, frontal and transverse planes are identified. Finally, it discusses qualitative analysis of human motion through prerequisite knowledge, planning observations, conducting analysis, and communicating findings.

1. Chapter 2
Kinematic Concepts
for Analyzing Human
Motion
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.
© 2012 The McGraw-Hill Companies, Inc. All rights reserved.McGraw-Hill/Irwin

2. 2-2
What is anatomical reference position?
• erect standing
position with all
body parts facing
forward
• considered the
starting point for all
body segment
movements
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

3. 2-3
posterior: toward
the back of the body
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.
Directional terms:
inferior: farther away from the head
anterior: toward the front of the body
superior: closer to the head
medial: toward the midline of the bodylateral: away from the
midline of the body
proximal: closer to the trunk
distal: away from the trunk
superficial: toward the surface of the body
deep: inside the body away from the surface

4. 2-4
Reference planes:
• sagittal plane - in which forward and
backward movements occur
• frontal plane - in which lateral movements
occur
• transverse plane - in which rotational
movements occur
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

5. 2-5
Reference axes:
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.
Longitudinal axis - directed vertically and around which rotational
movements occur
Anteroposterior axis – directed along the sagittal plane
and around which rotations in the frontal plane occur
Mediolateral axis – directed along the frontal plane and
around which rotations in the sagittal plane occur

6. 2-6
Forms of motion:
Linear motion: motion along a line
• Rectilinear motion: (along a straight line)
• Curvilinear motion: (along a curved line)
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

7. 2-7
Forms of motion:
Angular motion: rotation around an axis
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

8. 2-8
Forms of motion:
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.
Rectilinear motion
Curvilinear motion
Angular motion

9. 2-9
Forms of motion:
General motion: a combination of linear and
angular motion (includes most human
motion)
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

10. 2-10
What is a mechanical system?
• a body or portion of a body that is
deliberately chosen by the analyst
• examples: throwing arm, kicking leg, the
trunk during performance of a lift, the
entire body during performance of a
maximal vertical jump
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

11. 2-11
Flexion Extension Hyperextension
Dorsiflexion Plantar flexion
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.
What movements occur in the sagittal plane?

12. 2-12
What movements occur in the frontal plane?
Abduction Adduction
Lateral flexion
Elevation Depression
Radial
deviation
Ulnar
deviation
Eversion Inversion
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

13. 2-13
What movements occur in the transverse
plane?
Medial
rotation
Lateral
rotation
Pronation Supination
Horizontal
adduction
Horizontal
abduction
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

14. 2-14
Spatial Reference Systems
• useful for standardizing descriptions
of human motion
• most commonly used is the Cartesian
coordinate system
• human body joint centers are labeled
with numerical x and y coordinates
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

15. 2-15
Spatial Reference Systems
(0,0)
X
Y
(x,y) = (3,7)
Cartesian coordinates of the hip
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

16. 2-16
Spatial Reference Systems
Coordinates can be both positive and
negative.
x
y
(0,0)
x = +
y = +
x = -
y = +
x = -
y = -
x = +
y = -
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

17. 2-17
Qualitative Analysis:
Prerequisite Knowledge
• What is the purpose of the skill?
• What are the causes of performance errors?
• How can knowledge be gained?
• experience in performing the skill
• reading available literature
• attending conferences and workshops
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

18. 2-18
Qualitative Analysis:
Planning
• What is the question to be answered?
• From what perspectives (angle and viewing
distance) should the movement be
viewed?
• How many observations should be taken?
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

19. 2-19
Qualitative Analysis:
Planning
• What plans should be made for:
• performer attire
• lighting conditions
• background
• use of video
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.

20. 2-20
Qualitative Analysis:
Conducting the Analysis
Identify
Question/Problem
Make Decisions
Interpret Observations
Viewing Angle
Viewing Distance
Performer Attire
Environmental
Modifications
Use of Video
Auditory
From Performer
From Other Analysts
Collect
Observations
Communicate
with Performer
End Analysis
Visual
Refine Question
Basic Biomechanics, 6th edition
By Susan J. Hall, Ph.D.