At the conclusion of this chapter, the student should be able
- 1. Identify and discuss instrumentation for the collection
and analysis of kinematic data in human movement.
- 2. Identify and discuss instrumentation for the collection
and analysis of kinetic data in human movement.
- 3. Discuss the limitations of biomechanical instrumentation.
- 4. Critically examine the research literature in the field
of human movement with an understanding of the methodologies used.
The scholarly study of people in motion has interested scientists
for centuries, and their contributions have established the foundation
for the advances that continue to be made in kinesiology and biomechanics
research in the twenty-first century. Methodology has progressed
from exclusive dependence on observations by the naked eye to the
use of sophisticated photographic and electronic equipment for analyzing
and quantifying the anatomical and mechanical nature of human performance.
Although the student in the undergraduate course in kinesiology
is not expected to have much experience using some of the more sophisticated
equipment and methodology, much of the technology used in movement
analysis is readily available. Because of this increased availability
of analysis technology and the increased interest in undergraduate
research, the student should be aware of the available instrumentation
and more advanced approaches to movement analysis.
There are two broad areas of study in the field of biomechanics:
kinematics and kinetics. As noted in Chapter 10, kinematics is the
description of motion without consideration of the forces involved.
Kinematic variables include position, displacement, time, velocity,
and acceleration—all of which are discussed in Chapter 11. Kinetics is the study of the forces that produce motion. Kinetic
variables include force and torque, among others. Kinetic variables
are the focus of Chapters 12 and 13. Information about each of these
variables is gathered through the collection of data. There are
three primary categories of biomechanical data collection. The first
of these is motion capture data, which are valuable for the study
of kinematics. Commercially available motion capture systems vary
widely in complexity and cost. Motion capture may be based on video,
electromagnetic systems, or electrogoniometry. In kinematic studies,
measures of position and time are used to calculate the derivatives
velocity and acceleration (Chapter 11). Kinematic data from motion
capture systems may be linear or angular or both. The second primary
category of data collection includes force measuring systems. Force
measures are collected through the use of force transducers that
convert pressure, stress, or energy to a digital signal. Finally,
muscle activity is measured through the use of electromyography
(EMG), as mentioned in Chapter 3. Electromyography measures the
minute electrical signals generated by active muscle and can provide
information on the contraction state of muscle.
Kinematic data, or data that describe a motion, are collected
with a variety of instruments ranging from still cameras through
high-speed film and video to sophisticated motion-tracking systems. The
primary purpose of all such instrumentation is ...