Fundamentals of Biomechanics

L-4 FUNDAMENTALS OF BIOMECHANICS
LAB ACTIVITY 2
QUALITATIVE AND QUANTITATIVE ANALYSIS OF
RANGE OF MOTION
This text summarizes many biomechanical variables and concepts into nine principles of biomechanics.
The analysis of human movements using these biomechanical principles can be qualitative (subjective)
or quantitative (based on numerical measurements). All kinesiology professions have used
both qualitative and quantitative analyses of human movement, but qualitative analysis is used most
often. This lab will explore the Range-of-Motion Principle of biomechanics, using a variety of static
flexibility tests common in physical education and physical therapy. This lab will show you there are
a variety of ways to quantify range of motion and that there are strengths and weaknesses of both
qualitative and quantitative analyses of human movement.
Physical therapists used to perform a standing toe touch to screen for persons with limited hamstring
flexibility. Patients either passed the test by being able to touch their toes with their fingers
while keeping their legs straight, or they failed to touch their toes, indicating poor hamstring flexibility.
Flexible hamstrings allows a person to tilt their pelvis forward more, making it easier to touch
their toes. Recently, more accurate field tests of static flexibility have been developed. The tests that
will be used are the sit-and-reach test (SRT), active knee extension (AKE), and the modified Schober
test (MST). The results of these flexibility tests can be analyzed qualitatively (judging if the subject has
adequate flexibility) or quantitatively. Quantitative analysis can either be norm-referenced (comparing
scores to all other people) or criterion-referenced. Criterion-referenced testing compares test
scores to some standard of what should be. Criteria or standards are usually based on evidence on
what correlates with health (health-related fitness) or with physical abilities to perform jobs safely (occupational
screening). For example, physical therapists studying the sit-and-reach test suggested that
subjective observation of the forward tilt of the rear of the pelvis is as effective an assessment of hamstring
flexibility as the SRT score (Cornbleet & Woolsey, 1996).
BACKGROUND READING
Chapter 2 herein: “Fundamentals of Biomechanics and Qualitative Analysis”
Cornbleet, S. & Woolsey, N. (1996). Assessment of hamstring muscle length in school-aged children
using the sit-and-reach test and the inclinometer measure of hip joint angle. Physical Therapy, 76,
850–855.
Gajdosik, R. & Lusin, G. (1983). Hamstring muscle tightness: Reliability of an active–knee-extension
test. Physical Therapy, 63, 1085-1088.
Gleim, G. W., & McHugh, M. P. (1997). Flexibility and its effects on sports injury and performance.
Sports Medicine, 24, 289–299.
Knudson, D., Magnusson, P., & McHugh, M. (2000, June). Current issues in flexibility fitness. The
President's Council on Physical Fitness and Sports Research Digest, pp. 1-8.
TASKS
1. Select three volunteers for flexibility testing
2. Learn how to use a sit-and-reach box, inclinometer, goniometer, and tape measure for SRT, AKE,
and MST.
3. Collect the following quantitative assessments of lumbar and hamstring range of motion for one
side of the body: SRT, AKE, and MST. While these measurements are being taken, have people in
your lab group do a qualitative/categorical assessment (hypoflexible, normal, hyperflexible) of the
subject being tested.
4. Answer the questions.
Copyright © 2007 Springer Science+Business Media, LLC.All rights reserved.