CORRELATION BETWEEN
STRENGTH AND FLEXIBILITY
By: Billy Wilson
INTRODUCTION

There are four basic components to physical
fitness.
–


Muscular Endurance, Cardiovascular Endurance,
Muscular Strength, Flexibility
Muscular Strength- the ability of the muscle
to generate the maximum amount of force
Flexibility- the ability to move a joint through
the full range of motion without discomfort or
pain
PURPOSE AND HYPOTHESIS

Purpose
–

The major purpose of this study was to determine
a correlation between an individual’s muscular
strength and flexibility.
Hypothesis
–
The null hypothesis for this study states: There
was no correlation between an individual’s
muscular strength and flexibility.
PROBLEM AND NEED

Problem
–

The study was designed to answer the question: Was there
a correlation between an individual’s muscular strength and
flexibility?
Need
–
–
It is important to maximize both strength and flexibility since
they are both components of physical fitness.
It is important to know the relationship between flexibility
and muscular strength.
LIMITATIONS
The major limitations of the study were:

The researcher was not the one who collected the
data.

There were multiple testers.

The researcher was not present when the tests
were taken.

All testers may not have been using exactly the
same joint reference points when calculating range
of motion.

Goniometry is not the most accurate form of
determining flexibility.
DELIMITATIONS
The major delimitations of the study were:

All the subjects were volunteers.

All the subjects were students at a university in
Southeast Tennessee.

All subjects were tested in a class designed
specifically for research testing.

The tests were taken in the 2007 school year.

All subjects were between the ages of 18-38.

The strength test was delimited to the one
repetition max.
CHAPTER 2 INTRO


Physical fitness is defined as a set of attributes that
people have or achieve that relates to the ability to
perform physical activity.
Muscular Strength- the maximum amount of push or
pull that can be exerted one time by a muscle group
–

Isometric Contraction and Isotonic Contraction tests
Flexibility
–
–
Static Flexibility and Dynamic Flexibility
Inclinometer, Radiography, Goniometry
RECOMMENDATION FOR PROGAMS




The majority of the subjects were college aged
males and females that were not regularly involved
in strength or flexibility training.
The main instrument used was the goniometer and
the main test was the 1RM.
Most of the studies were on the effects of pre-event
stretching on exercise performance.
Most concluded that pre-event stretching caused a
power deficit
SUMMARY OF LITERATURE REVIEW

Pre-event stretching has a negative effect on
performance.
–


speed, agility, and power output
Findings based upon college aged subjects
that were mostly physically inactive.
Goniometery and 1RM were main testing
tools.
CHAPTER 3

Sample
–
–
–
–
Data collected in Fall semester of 2007-2008
school year
Males between the ages 18-38
Students attending major metropolitan university
Randomly chosen by students of the exercise
testing class
CHAPTER 3

Methodology
–
–
Subjects participated in 1RM bench press test for
muscular strength
Subjects’ flexibility measured with a goniometer

–
–
Right shoulder abduction
Data were collected by students of an exercise
testing class
Both male and female subjects tested, but only
male scores were used for this study
CHAPTER 4
Table 4.1
Subjects’ One Repetition Max vs. Flexibility
Ss
Age
1
22
2
23
3
19
4
23
5
21
6
21
7
21
8
22
9
20
10
20
11
22
12
31
13
20
14
38
15
19
Ss= Subjects
Age= The age of the subjects at the time of testing
1RM= One repetition maximum bench press in pounds
Flexibility= Degree of shoulder range of motion.
1RM
415
365
265
405
395
215
225
185
190
250
145
175
195
245
255
Flexibility__________
180
180
180
180
168
180
180
150
120
138
110
183
162
154
183
CHAPTER 4
Table 4.2
Spearman r Data Analysis of Strength and Flexibility Correlation
Level of Confidence
Degree of Freedom
Critical Value
Calculated Value
0.05
58
.250
.010
Legend:
Level of Confidence= p>0.05
Degree of Freedom= the number of subjects minus one
Critical Value= a value in the sample distribution to which the calculated statistic
was compared
Calculated Value= a value derived from computing procedures applied to the data
CHAPTER 5

Null Hypothesis
–
–

There was no correlation between an individual’s muscular
strength and flexibility.
Based on the analysis of the data, the null hypothesis was
accepted.
If this study were done again:
–
–
–
Make sure no stretching was done before the 1RM test
Test a different shoulder movement
Test the correlation in females
REFERENCES
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Medicine, 5: 33-42.
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