CORRELATION BETWEEN TIMED SIT UP TEST
AND SIT UP TEST WITH NO TIME LIMIT
BY
WU SHING
05010233
AN HONOURS PROJECT SUBMITTED IN PARTIAL FULFILMENT OF THE
REQUIREMENTS FOR THE DEGREE OF
BACHELOR OF ARTS
IN
PHYSICAL EDUCATION AND RECREATION MANAGEMENT (HONOURS)
HONG KONG BAPTIST UNIVERSITY
APRIL 2008
2
HONG KONG BAPTIST UNIVERSITY
25th April, 2008
We hereby recommend that the Honours Project by Mr. WU SHING
entitled “Correlation Between the Timed Sit-up Test and the
Sit-up Test With No Time Limit” be accepted in partial
fulfillment of the requirements for the Bachelor of Arts
Honours Degree in Physical Education And Recreation
Management.
Dr. Tong Kwok Keung Dr. Lau Wing Chung
Chief Adviser Second Reader
3
ACKNOWLEDGEMENTS
First of all, I would like to express my deepest gratitude
to my chief advisor, Dr. Tong Kwok Keung, for his valuable
advices and professional suggestions and guidance on the study.
In addition, I would also like to express my gratitude to my
second reader, Dr. Lau Wing Chung, to his effort on this study.
On the other hand, I would also like to give thanks to P.E.
teacher of Tai Po Government Secondary School, Ms. Siu Oi Yee,
for her arrangement of the field tests. By the way, I would
also like to express my appreciation to the students of Tai
Po Government Secondary School for their participation in this
study.
Wu Shing
Department of Physical Education
Hong Kong Baptist University
Date: 23rd April, 2008
4
ABSTRACT
Timed Sit-up Test is a very popular test for examining one’s
abdominal muscular endurance. However, according to the
definition of muscular endurance, it is wondered if the
limitation of time will affect the performance of the sit-up
test. This study was designed to examine the validity of
1-minute sit-up test by assessing the correlation between the
1-minute sit-up result with that having no time limit. Seventy
male and forty-five female students of Tai Po Government
Secondary School were participated in the study (age, 14.8
± 0.7 years; height, 155.1 ± 8.2 cm; weight, 52.3 ± 8.2 kg).
Subjects were asked to perform Timed Sit-up Test (Test 1) and
Sit-up Test with no time limit (Test 2) respectively. Both
tests performance were defined as repetition of sit-up
performed. In this study, the mean of Test 1 and Test 2 was
38.1 ± 9.5 rep and 50.6 ± 17.1 rep respectively. It was found
that there was a significant positive relationship between
both tests (r = 0.709, p < 0.05), and the coefficient of
5
determination was 50.3% (r2 = 0.503). According to the findings,
it was suggested that the timed sit-up test was valid for
examining one’s abdominal muscle endurance.
6
TABLE OF CONTENTS
CHAPTER PAGE
1. INTRODUCTION ........................... 9
Statement of Problem ................. 10
Purpose of the Study ................... 11
Significance of the Study ............. 12
2. REVIEW OF LITERATURE ................... 14
Benefits of having good abdominal
muscular endurance ...................
15
Timed Sit-up Test .................... 17
Various alternatives of abdominal
exercises ............................
18
Factors affecting abdominal muscular
endurance ............................
22
Summary of literature review ......... 27
Definition of Terms .................. 28
Research Hypothesis .................. 31
3. METHOD ................................. 32
7
Subjects ............................. 32
Procedures ........................... 32
Delimitations ........................ 35
Data Analysis ......................... 36
Statistical Hypothesis ............. 36
Statistical Analysis ............... 36
Limitations .......................... 37
4. RESULTS .............................. 38
Discussion ........................... 42
5. SUMMARY AND CONCLUSIONS ................ 47
Summary of Results ................... 47
Conclusion ........................... 48
Recommendations of Further Study ..... 48
REFERENCES ................................ 50
APPENDIX .................................. 54
A. Data Collection Form ................ 54
B. Parental Consent Form ............... 55
8
LIST OF TABLES
TABLE PAGE
1. Physical characteristics of the subjects .... 38
2. Descriptive statistics of the subjects’
performance in the Timed Sit-up Test and the
Sit-up Test with no time limit ...............
39
3. Pearson’s correlation test between the
subjects’ performance in the Timed Sit-up Test
and the Sit-up Test with no time limit ......
40
9
Chapter 1
INTRODUCTION
Muscular strength and endurance are one of the
health-related physical fitness components (ACSM, 2003).
Franks (1989) also pointed out that certain amount of muscular
strength and endurance was necessary to perform numerous daily
tasks. In order to measure one’s physical fitness level, many
physical fitness tests were developed. Individual’s physical
fitness level would be interested for different bodies with
different purposes. In Hong Kong, physical education of
primary and secondary schools used “School Physical Fitness
Award Scheme” as their protocols to determine students’
physical fitness levels; Security forces servants were
necessary to pass a series of physical test before they were
employed.
In the above physical fitness tests batteries, timed
sit-ups test had been included. The American Alliance for
Health, Physical Education, Recreation and Dance (AAHPERD)
10
also put timed sit-ups into a four items test battery which
evaluated physical fitness related to lifelong health
(AAHPERD, 1976). They suggested that muscular strength and
endurance was one of the important factors when considering
one’s physical fitness level. William, Stuart, Andre and
William (1999) pointed out that abdominal muscle
strengthening would contribute to performance enhancement,
postural improvement and lowering the risk of low back pain.
Timed Sit-up Test was one of the widely used methods which
was developed to determine one’s abdominal muscular strength
and endurance. The test required subjects to perform maximal
repetitions of sit-up in one minute. The more repetitions the
subject has done, the higher marks he will get.
Statement of problem
Many longitudinal studies showed that abdominal muscles
were recruited while sit-up was performed. Most studies of
sit-up used electromyogram (EMG) to describe the movement
dynamics. Although hip flexor might be involved in performing
11
sit-ups of different styles, abdominal muscle recruitment
must be involved (William et al., 1999; Carlos, Marco, Maria
& Ricardo, 1991). For most previous EMG investigation, hip
flexor’s activity was not taken into consideration.
Docherty (1996) defined that muscular endurance as the
ability of a muscle, or muscle group, to generate force
repeatedly or for an extended period of time. By looked at
the definition briefly, limited time shall not be existed in
a muscular endurance test. Once limited time was given in timed
sit-ups test, speed of repetition of sit-ups would become an
important factor with respect to his abdominal muscular
endurance. It was wondered if the validity of 1 minute sit-up
test was affected by the time limit.
Purpose of Study
The purpose of this study was to examine the validity of
1 minute sit-up test by assessing the correlation between the
1 minute sit-up result with that having no time limit.
12
Significance of the Study
Similar to William et al. (1999), Gloria, Jorge, Danny,
Matthew & Freddie (1997) stated that strong abdominal muscles
played a very important role in both postural control and
prevention of low back injury. In other words, abdominal
muscular strength and endurance is important to human’s health.
Since individual’s abdominal muscular strength and endurance
is such important, relevant test protocols was developed to
find out individual’s abdominal muscular strength and
endurance.
Since timed sit-ups test was widely used, the test must
be valid to measure individual’s abdominal muscular strength
and endurance. As muscular endurance means the ability of
muscle to perform a muscle contraction repeatedly over a
period of time, time shall not be taken into consideration.
As a result, the validity of timed sit-ups test was queried.
As aforesaid, abdominal muscular strength and endurance
was vital to individuals. Physical educators needed to assess
13
students’ physical fitness levels in order to give them grades;
Security forces servants needed to pass in the physical
fitness test in order to prove their abilities to serve society.
While the widely-used test protocol was not testing what it
supposed to measure, all results from the test were said to
be meaningless. In such case, individual’s actual abdominal
muscular strength and endurance would be hidden.
This study is proposed to determine the correlation between
the performance of timed sit-ups test and that of sit-ups with
no time limit, to investigate whether one-minute sit-up test
was valid to examine the one’s abdominal muscular endurance.
14
Chapter 2
REVIEW OF LITERATURE
Muscular endurance is important to our health. As described
by Docherty (1996), muscular endurance is the ability of a
muscle, or muscle group, to generate force repeatedly or for
an extended period of time. Many sports and daily life body
movement required certain level of muscular endurance.
Abdominal muscular endurance is especially important to
maintain healthy body. Demont, Lephart, Giraldo, Giannantonio,
Yuktanandana & Fu (1999) stated that strong abdominal
musculature are considered important in both prevention and
rehabilitation of lumbar pathologies. They also pointed out
that several authors suggested that back pain was associated
with weak abdominal muscles, and strengthening of abdominal
muscles might be beneficial in reducing pain.
The present study was to determine the correlation between
the performance of timed sit-ups test and that of sit-ups with
no time limit, to investigate whether one-minute sit-up test
15
was valid to examine the one’s abdominal muscular endurance.
The review of literature for the present study focused on the
following aspects: (a) Benefits of having good abdominal
muscular endurance; (b) Timed Sit-up Test; (c) Various
alternatives of abdominal exercises; (d) Factors affecting
abdominal muscular endurance; and (e) Summary of literature
review.
Benefits of having good abdominal muscular endurance
Abdominal muscular endurance is important to human’s
physical fitness. Demont et. Al.(1999) pointed out that strong
abdominal muscles are vital in both prevention and
rehabilitation of lumbar pathologies. They added that low back
pain is associated with weak abdominal muscles. Therefore,
strengthening of abdominal muscles can be beneficial in
reducing low back pain. In addition, Kasee and Larry (2004)
stated that a minimal amount of abdominal endurance was
necessary for maintaining proper alignment of the axial
skeleton and supporting movements of both the lower and upprt
16
extremities in activities of daily living, work, and athletic
performance.
Similarly, Behm, Leonard, Young, Bonsey and MacKinnon
(2005) also suggested that the strengthening of trunk muscles
is an important consideration for activities of daily living,
sports performance, and the rehabilitation of low back pain.
Amie and Mahyar (2007) had similar finding in their clinical
research. They found that clinical trunk muscle endurance
tests showed a relatively good sensitivity and specificity
and predictive value in low back pain. Luoto et al. (1996)
also suggested that psychomotor reaction time was faster in
those subjects without back pain.
Apart from above benefits, Tadashi, Noriyuki, Naotaka,
Tomoyuki and Paul (1996) added that abdominal muscles had
significant respiratory activity in humans. They pointed that
the four abdominal muscle layers played an important role in
compression of the abdominal contents, resulting in
displacement of the diaphragm into the thorax and decrease
17
in lung volume.
Timed Sit-up Test
According to Teacher’s Handbook of Physical Education –
School Physical Fitness Award Scheme (2007), the objective
of the timed sit-up test was to measure the abdominal muscular
strength and endurance by performing as many sit-ups as
possible in one minute. The procedures of timed sit-up test
were described as follow:
“The student lies on the mat with knees bent and the feet
are held flat down firmly by a partner. The heels should
be 30 to 45 cm from the buttocks, such that the angle
between the thigh and the floor is about 45 degrees. Arms
are crossed in front of the chest with hands on the opposite
shoulders. The chin is tucked to the chest. The student
lies in supine position. In response to the starting signal,
he/she curls up until the elbows touch the thighs, and
then uncurls until the mid-back contacts the mat. This
is counted as one time. The teacher should encourage the
18
student to repeat as many sit-ups as possible within one
minute. The student may rest in a lying or sitting position
during the test.”
Gail et al. (1992) stated that sit-up tests have been used
in most youth and adult fitness test batteries because low
back pain was always associated with abdominal strength. They
suggested that timed sit-up tests had not been validated
against a criterion measure to determine if they actually
measure abdominal strength. Rather, power, average force, or
torque was used to estimate strength. After comparing the
results of using Isokinetic dynamometer and that of performing
timed sit-up tests, they found that there were significant
differences.
Various alternatives of abdominal exercises
There were various alternatives of abdominal exercises
other than sit-up. Some of them needed specific devices to
help, such as “Ab-roller”; some of them did not need, for
example, curl-up. Many longitudinal studies had been done in
19
order to compare which abdominal exercise would recruit more
muscle fibers and hence train the abdominal muscles more
effectively.
Carlos et al. (1991) had done a research to find out the
contribution of the rectus abdominis and rectus femoris in
twelve selected abdominal exercises. The abdominal exercises
they chose were listed: (1) sit-up: long lying position
without feet support, (2) sit-up: long lying position with
feet supported, (3) sit-up: hook lying position with feet
supported, (4) sit-up: hook lying position without feet
supported, (5) curl-up, (6) elevation of lower limbs: forearm
supported position, (7) elevation of lower limbs: long lying
position, (8) V-sit, (9) conventional sit-up, (10) inclined
sit-up: long lying position with feet supported and extended
knee and hip (11) inclined sit-up: long lying position without
feet supported flexed knee and hip, and (12) elevation of lower
limbs: suspended position. After electromyographic analysis,
they discovered that V-sit was the most effective abdominal
20
exercise with respect to train upper rectus abdominis and
lower rectus abdominis. Comparing with V-sit, sit-up: hook
lying position with feet supported and flexed knee and hip
had not significant difference with respect to upper rectus
abdominis. However, they found that sit-up with feet supported
was significantly lower muscle action potentials than V-sit
with respect to lower rectus abdominis. Similar research
finding was done by Walters and Partridge (1957). They
generalized that sit-ups, curl-ups and V-sit were the most
efficient exercises for abdominal muscles. In addition, they
reported that less activity of abdominal muscles in sit-up
exercises when feet were supported than when feet were
unsupported.
Some abdominal exercises could be helped by using devices.
Manufacturers of the devices usually suggested that by using
those devices there would be improvements in muscle strength
while simultaneously protecting the back and neck. Demont et
al. (1999) had done a study to compare the training effects
21
of the Ab-Flex, Ab-Roller and standard crunch on
electromyogram production, isometric maximum voluntary
contraction and Isokinetic average peak torque at 30°/sec of
the abdominal muscles. They found that using those devices
did not add significantly to overall abdominal strength
development or reduction of body fat. Similar results were
suggested by Kasee and Larry (2004). In their study, the suface
electromyographic activity of the abdominal musculature and
rectus femoris muscle during trunk-flexion, the traditional
trunk curl and exercises using Ab-Roller, Ab-slide and Fit
Ball were compared. Similarly, they found that those devices
did not elicit greater activity of the upper rectus abdominis
and lower rectus abdominis than performing traditional trunk
curls. On the other hand, they found that use of the Ab-slide
elicited greater external oblique activity and significantly
less upper rectus abdominis activity than the other 3 modes.
Bird, Fletcher and Koch (2006) also compared the Ab-slide with
crunch abdominal exercises for electromyographic activity for
22
abdominal muscles. They found that the external oblique and
lower rectus abdominis had significantly higher integrated
activation amplitudes for the crunch exercise during
concentric movement. In contrary, the upper rectus abdominis,
lower rectus abdominis and external oblique had significantly
higher average integrated amplitudes for the Ab-slide
exercise during eccentric movement.
Factors affecting abdominal muscular endurance
Other muscles involved during abdominal endurance test
While an abdominal muscular endurance test was performed,
muscles other than abdominal wall might help as synergetic
functioning. Carlos et al. (1991) stated that the rectus
femoris participated to a great degree when sit-up was
performing. In their study, they suggested that the sit-ups
performed with extended knees and supported feet required more
activity of the rectus femoris than the sit-ups performed with
extended knees and unsupported feet. On the other hand, Chong,
Lee, Will, Ashley and Nicole (2006) added that lower
23
paraspinal, latissimus dorsi and upper trapezius showed
action potential while a full sit-up was performing.
Localized muscle fatigue
Bryan, Stephen and Lee (2006) defined skeletal muscle
fatigue as a reduction in force- and/or velocity-generating
capacity of a muscle that has been under load and is relieved
with rest. Bryan et al. (2006) added that abdominal muscle
fatigue was caused by a reduction in calcium ion release from
the sarcoplasmic reticulum and/or damage to the structure of
the muscle fiber and the excitation-contraction coupling
mechanism. As abdominal muscles were fatigue quickly, the
performance of muscular endurance test would be affected.
Maestu et al. (2006) stated that the metabolic state of
the active muscles played an important role in regulating the
recruitment of high threshold motor units, because a close
link existed between the state of energy supply and types of
muscle fibers being recruited. They pointed out that anaerobic
threshold could therefore be considered to be an important
24
assessment of the ability of the cardiovascular system to
supply oxygen at a rate adequate to prevent muscle
anaerobiosis during the exercise, and failure of this
mechanism to produce enough oxygen for muscles results in the
recruitment of type II muscle fibers that are less oxygen
dependent, but less effective, leading to quick fatigue.
Different abdominal muscular endurance tests
As many abdominal exercises were available, many different
types of abdominal muscular endurance tests were developed.
Macfarlane (1993) stated that the timed sit up test was
commonly used in fitness testing batteries, including the
AAHPERD Physical Best. Liemohn (1991) criticized that
modified 1-minute timed sit-up test which was specifically
adopted as a test that isolated the abdominal muscles and was
assumed to be a safer test than the straight-legged sit-up.
On the other hand, Gloria et al. (1997) pointed out that
sit-up exercise should be avoided for patients with acute or
subacute low back pain. They added that due to concern about
25
the safety of executing a sit-up, the abdominal crunch came
into favor. Other than abdominal crunch, curl-up test was an
alternative of abdominal muscular endurance test. Philip,
Mindy and Teresa (1997) developed a cadence curl-up test for
college students, which was valid to measure the abdominal
muscular endurance. After experiments, they found that the
cadence curl-up test activated the abdominal muscles with less
reliance on hip flexor musculature when compared with AAHPERD
sit-up test (1-minute sit-up test).
Tony, Harold, Robert and Brett (2001) suggested that the
half sit-up was reliable and should be considered as an
alternative to the full sit-up for fitness testing in middle
school physical education programs as well. They stated that
using full sit-up as a measurement of abdominal strength and
endurance because studies had shown that the abdominals were
not isolated and measurements were confounded by other muscle
activity. In other words, the hip flexors became involved with
a full sit-up, especially if the feet were held down.
26
Motivation
Motivation to perform abdominal muscular endurance test
was also an important factor, which would affect the test
result to certain degree. Leger and Gadoury (1989) pointed
out that lack of motivation might result in test ceasing,
before participants have reached their physiological limits.
On the other hand, they added that maximum effort tests require
well-motivated subjects.
Setting of the test
Setting of the test would affect the performance of the
test as well. In timed sit-up test, time limited was a factor
that might affect the test result. Docherty (1996) defined
that muscular endurance as the ability of a muscle, or muscle
group, to generate force repeatedly or for an extended period
of time. Hence, limited time shall not be existed in a muscular
endurance test. Once limited time was given in timed sit-ups
test, speed of repetition of sit-ups would become an important
factor with respect to his abdominal muscular endurance.
27
Carlos et al. (1991) found that control of the speed of
execution of exercises was one of the factors that affected
the result of abdominal test. YMCA (1989) also pointed out
that slow curl-up test was more preferable because timed
sit-up test was emphasized the speed all tend to involve muscle
groups other than the abdominals.
Summary of literature review
Strong abdominal muscles was an important consideration
for activities of daily living, sports performance, and the
rehabilitation of low back pain (David et al., 2005). The 1
minute sit-up test had been widely used as a test of abdominal
muscular strength and endurance (AAHPERD, 1980). There were
many factors affecting the individual’s performance of the
test, such as other muscles involved during the test,
localized muscle fatigue, motivation or setting of the test.
YMCA (1989) pointed out that timed sit-up was emphasized speed
all tend to involved muscle groups other than the abdominals.
This study was designed to examine the validity of 1 minute
28
sit-up test by assessing the correlation between the 1 minute
sit-up result with that having fixed frequency and no time
limit.
Definition of Terms
The following terms were defined operationally:
Health-related physical fitness
According to American College of Sport Medicine (2003),
health-related physical fitness actually has four components:
aerobic fitness, muscular fitness, flexibility and body
composition. Muscular fitness is the strength and endurance
of individual’s muscles.
Muscular Strength
Docherty (1996) stated that the International System of
Units (SI) defined strength as the maximal force or torque
developed by a muscle, or muscle group, during one maximal
voluntary action of unlimited duration at a specified velocity
of movement.
Muscular Endurance
29
Docherty (1996) defined that muscular endurance is the
ability of a muscle, or muscle group, to generate force
repeatedly or for an extended period of time.
Abdominal Wall
The muscles of anterior abdominal wall consist of rectus
abdominis, external abdominal oblique, internal abdominal
oblique and transverses abdominis. These muscles responsible
to flex and rotate vertebral column, compress abdomen and
depress thorax (Rod, Trent & Philip, 2006).
Sit-up
William ed al. (1999) defined the term of sit-up as the
specific movement from a supine position of hip flexion
without lumbar flexion. It is the body movement which involves
abdominal muscular contraction.
Timed Sit-up Test
Timed sit-up test is widely described as a test of abdominal
muscular strength and endurance (Gail, Ronald, David & Arthur,
1992). It is a test which individual is asked to perform as
30
many sit-ups as possible in one minute. According to Teacher’s
Handbook of Physical Education – School Physical Fitness Award
Scheme (2007), the objective of the timed sit-up test was
supposed to measure the abdominal muscular strength and
endurance.
Fatigue
According to Rod et al. (2006), fatigue is defined as the
decreased capacity to do work and the reduced efficiency of
performance that normally follows a period of activity.
Action Potential
Action potential is defined as the change in membrane
potential in an excitable tissue that acts as an electric
signal and is propagated in an all-or-none fashion (Rod et
al., 2006).
Motivation
Motivation refers to what energizes human behavior, or what
directs or channels such behavior and to how this behavior
is maintained or sustained over an extended period of time
31
(Tisgilis, 2005).
Intrinsic Motivation
Tisgilis (2005) stated that intrinsic motivation refers
to performing an activity purely for the enjoyment and
satisfaction derived from participation. An intrinsically
motivated individual performs the behavior voluntarily, in
the absence of material rewards or external constraints.
Research Hypothesis
According to the above literatures reviewed, it was
hypothesized that:
1. There would be no significant correlation between the
performance of the timed sit-ups and that of sit-ups with no
time limit in participants.
32
Chapter 3
METHOD
The purpose of this study was to examine the validity of
1-min sit-up test by assessing the correlation between the
1-min sit-up result with that having fixed frequency and no
time limit. This chapter was divided into the following parts:
(a) subjects; (b) procedures; (c) method of analysis; and (d)
statistical hypothesis.
Subjects
One hundred and fifteen secondary schools students, who
studied in Tai Po Government Secondary School and aged between
14 and 17 years old, were invited to participate in the timed
sit-up test (test 1) and the sit-up test with no time limit
(test 2). Before the study, subjects and their guardians were
asked to sign on the consent forms after knowing the purpose,
benefits and risks of the study.
Procedures
In this study, subjects were invited to perform test 1 and
33
test 2 in randomly sequences on two separate days within a
week. Both tests were conducted in the covered playground of
the Tai Po Government Secondary School.
Timed sit-up test (test 1)
The subjects were strongly advised not to have a heavy meal
2 hours before the sit-up tests. The subjects were invited
to do warm up exercises. Warm up exercises included 5 minutes
jogging around the covered playground and then 5 minutes
related stretching exercises. After the warm up exercises,
subjects were invited to perform the test 1.
The description of the test 1 was described by the Teacher’s
Handbook of Physical Education – School Physical Fitness Award
Scheme (2007):
“The student lies on the mat with knees bent and the feet
are held flat down firmly by a partner. The heels should be
30 to 45 cm from the buttocks, such that the angle between
the thigh and the floor is about 45 degrees. Arms are crossed
in front of the chest with hands on the opposite shoulders.
34
The chin is tucked to the chest. The student lies in supine
position. In response to the starting signal, he/she curls
up until the elbows touch the thighs, and then uncurls until
the mid-back contacts the mat. This is counted as one time.
The teacher should encourage the student to repeat as many
sit-ups as possible within one minute. The student may rest
in a lying or sitting position during the test.”
AAHPERD (1976) added that no resting was permitted between
sit-ups, and only correct sit-ups could be counted.
Figure 1 showed the setting of the sit-up test:
Figure 1.
The setting of the timed sit-up test.
35
In this study, the above procedures were followed. However,
the partner was changed to a test assistant, who was found
in the secondary school and learnt how to be the test assistant
prior to the test. After subjects performed the test,
localized stretching exercises were advised to do.
Sit-up test with no time limit (test 2)
Test 2 was similar to the test 1. All the testing procedures
were remained the same as the test 1, except one minute
limitation. Subjects were asked to perform as many sit-ups
as they could continuously until volitional exhaustion.
Subjects were said to be volitional exhaustion when they were
not able to perform an entire sit-up motion. Similarly, as
AAHPERD (1976) added, no resting was permitted between sit-ups,
and only correct sit-ups could be counted. If obvious resting
was detected, the test was said to be finished.
Delimitations
The following delimitations were included in this study:
1. The subjects of the study were delimited to the male and
36
female students who studied in Tai Po Government Secondary
School and aged between 14 to 17 years old.
2. Total of 115 subjects were involved in this study.
3. The Timed Sit-up Test was carried at the covered playground
of the Tai Po Government Secondary School.
4. The Sit-up Test with no time limit was carried at the
covered playground of the Tai Po Government Secondary
School.
5. The Timed Sit-up Test and the Sit-up Test with no time limit
were tested on two separate days within a week.
Data Analysis
Statistical hypothesis
The following null hypothesis was examined:
1. There would be a significant correlation between the
performance of the timed sit-ups and that of sit-ups with
no time limit in participants.
Statistical Analysis
Data were reported as mean and standard deviation. Minimum
37
and maximum values of variables were analyzed by the
Statistical Package for Social Science (SPSS). Pearson
Production Moment Coefficient of Correlation (r) was used to
examine the correlation between the 1-min sit-up result with
that having fixed frequency and no time limit. An alpha level
of p
38
Chapter 4
RESULTS
Seventy male and forty-five female students of Tai Po
Government Secondary School were invited to participate in
this study. The purpose of this study was to examine the
validity of 1 minute sit-up test by assessing the correlation
between the 1 minute sit-up result with that having no time
limit. All subjects engaged in 1 minute sit-up test and sit-up
test with no time limit.
The physical characteristics of the subjects were shown
in the table 1:
Table 1
Physical characteristics of the subjects (N=115)
Range Mean ±SD
Age (yr) 14 – 17 14.8 0.7
Height(cm) 140 – 172 155.1 8.2
Weight(kg) 40.5 – 70.5 52.3 8.2
39
The descriptive statistics of the subjects’ performance
in the Timed Sit-up Test (Test 1) and the Sit-up Test with
no time limit (Test 2) were shown in table 2:
Table 2
Descriptive statistics of the subjects’ performance in the
test 1 and test 2 (N=115)
Range Mean ±SD
Test 1 (rep) 20 – 66 38.1 9.5
Test 2 (rep) 7 - 100 50.6 17.1
Test 1: Timed Sit-up Test
Test 2: Sit-up Test with no time limit
The Pearson correlation between the subjects’ performance
in the Timed Sit-up Test (Test 1) and the Sit-up Test with
no time limit (Test 2) was computed. The Pearson correlation
coefficient and the coefficient of determination were shown
as the following Table:
40
Table 3
Pearson’s correlation test between the subjects’ performance
in the Timed Sit-up Test (Test 1) and the Sit-up Test with
no time limit (Test 2) (N=115)
r r2 p
Correlation between
Test 1 and Test 2
.709** .503 0.01
** Correlation is significant at the 0.05 level (2-tailed)
The relationship between the subjects’ performance of the
Timed Sit-up Test (Test 1) and that of the Sit-up Test with
no time limit (Test 2) showed the positive relationship
roughly. Using the Pearson product-moment correlation
coefficient, the finding showed that the correlation between
the two tests was significant. The following figure showed
the relationship between the subjects’ performance of Test
1 and that of Test 2:
41
Figure 2
Scatter plotted graph showing the relationship between the
subjects’ performance of the Timed Sit-up Test (Test 1) and
that of the Sit-up Test with no time limit (Test 2)
25 50 75 100
Sit-up Test with no time limit
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As aforesaid, the correlation between the subjects’
performance of Test 1 and Test 2 was significant. Hence, the
null hypothesis “there will be significant correlation
between the performance of the timed sit-ups and that of
42
sit-ups with no time limit in participants” was accepted.
Discussion
The purpose of this study was to examine the validity of
1-minute sit-up test by assessing the correlation between the
1-minute sit-up result with that having no time limit. In the
following discussion part, three parts would be divided: (1)
Relationship between the performance of Timed Sit-up Test and
that of Sit-up Test with no time limit, (2) factors affected
the performance of both sit-up test, and (3) review of the
settings of both tests.
Relationship between the performance of Timed Sit-up Test and
that of Sit-up Test with no time limit
Timed Sit-up Test had always been included in many physical
fitness tests batteries. The American Alliance for Health,
Physical Education, Recreation and Dance (AAHPERD) put timed
sit-ups into a four items test battery that evaluated physical
fitness related to lifelong health (AAHPERD, 1976). In
addition, schools and security forces used timed sit-up test
43
to assess candidates’ abdominal muscular endurance as well.
However, there were few longitudinal researches to
investigate the factor of time in the sit-up test.
According to the present study, it was found that there
was significant correlation between the performance of timed
sit-up test and that of sit-up test with no time limit (r =
0.709, p < 0.05). However, only 50.3% (r2 = 0.503) of the
variance was shared. In other words, the coefficient of
nondetermination was 49.7%, which was attributed to factors
other than abdominal muscle endurance, such as the difference
between the settings of both tests and subjects’ motivation
to perform the tests.
Factors affected the performance of both sit-up tests
Since both tests involved in this study were sit-up tests,
the factor of different abdominal muscular endurance tests
was eliminated. As subjects were asked to perform the same
motion in the both tests, the factor of other muscles involved
during abdominal endurance test was also cancelled mutually.
44
The main difference of the both tests was the setting. For
timed sit-up test, one minute was limited; for the alternative
test, no time was limited. The setting would affect subjects’
performance directly, especially from the view of motivation.
Subjects would have be more motivated to perform sit-ups in
the timed sit-up test, as they would not fall into the
exhaustion phase. For the sit-up test with no time limit, when
subjects did their best in the test, localized muscle fatigue
would probably be created and they would feel painful. Because
of those negative reinforcements, their motivation of
performing sit-up test would be reduced. Leger and Gadoury
(1989) pointed out that lack of motivation might result in
test ceasing, before participants have reached their
physiological limits.
Review of the settings of both sit-up tests
The only difference of the both sit-up tests was the time
limitation. For timed sit-up test, one minute was given to
candidates to perform as many repetitions of sit-up as they
45
can. For sit-up test with no time limit, candidates were only
asked to perform as many repetitions of sit-up as they can,
no time limitation was given.
Although the present study found that both test results
were correlated, The coefficient of determination was only
0.503. In other words, the variance shared by or common to
the variables is only 50.3%. In contrary, the coefficient of
nondetermination was 49.7%. It meant that there were still
nearly 50% of the variance was not shared and was attributed
to other factors. As a result, it was proved that time factor
might induce other factors that would affect the validity of
the sit-up test.
Docherty (1996) defined that muscular endurance is the
ability of a muscle, or muscle group, to generate force
repeatedly or for an extended period of time. Based on the
definition, sit-up with no time limit was a standard to measure
abdominal muscular endurance because extended period of time
was given. Since statistic in the present study proved that
46
both tests were correlated, it was proved that the timed sit-up
test also had high validity to measure abdominal muscle
endurance.
Based on the above conclusion, for the consideration of
time control, time limitation seems to be a better system in
realistic life. For school curriculum, the physical test will
be always carried out in P.E. lessons. It is rushed to test
all students in an uncontrolled time. On the other hand, for
the other physical tests such as security forces physical
tests, large amount of candidates will be invited to perform
physical tests. From the view of administration and management,
it is better to give time limitation when the validity of the
timed sit-up test was proved by previous researches.
47
Chapter 5
SUMMARY AND CONCLUSIONS
Summary of Results
The present study was designed to examine the validity of
1-minute sit-up test by assessing the correlation between the
1-minute sit-up result with that having no time limit.
Seventy male and forty-five female students of Tai Po
Government Secondary School were participated in this study.
They performed timed sit-up test and sit-up test with no time
limit respectively in the covered playground of the Tai Po
Government Secondary School. The repetitions of both sit-up
tests were recorded, and the test results data were analyzed
by Statistical Package of Social Science (SPSS). Pearson
Product Moment Coefficient of Correlation (r) was used, and
0.05 level of significance was set.
The results of this study were summarized as follows:
1. There was significant positive relationship between
subjects’ performance of the timed sit-up test and that
48
of the sit-up test with no time limit (r = 0.709, p <
0.05, N = 115).
2. The common variance of the two tests was 50.3%
(coefficient of determination = 0.503). 49.3% of the
variance was not shared and was attributed to factors
other than abdominal muscle endurance.
Conclusion
From the findings, it was found that there was significant
positive relationship between subjects’ performance of the
timed sit-up test and that of the sit-up test with no time
limit. Since statistic in the present study proved that both
tests were correlated, it was concluded that the timed sit-up
test was valid for examining one’s abdominal muscle endurance.
Recommendation of Further Study
1. The age group, the sex group should be extended, since there
might have differences in abdominal muscle endurance.
2. Body fat percentage of the subjects should be considered
as well, since there might have difficulty in performing
49
sit-up when individual’s body fat percentage is high.
50
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54
APPENDIX A
Data Collection Form
Name: Subject No.:
Age: Gender:
Height: cm Weight: kg
1st Test: (Date) T / N
2nd Test: (Date) T / N
T = Timed Sit-up Test
N = Sit-up Test with no time limit
Data Collection Form
Name: Subject No.:
Age: Gender:
Height: cm Weight: kg
1st Test: (Date) T / N
2nd Test: (Date) T / N
T = Timed Sit-up Test
N = Sit-up Test with no time limit
APPENDIX B
仰臥起坐測試內容及家長同意書
本人是香港浸會大學體育及康樂管理學系三年級學生，現正進行一項有關仰臥起坐測試的研究。本人希望邀請 貴子弟參加是次仰臥起坐測試，唯 貴子弟必須得到 閣下批准，方可進行測試。
請 閣下詳閱下列細則：
1. 測試目的及內容
貴子弟將會進行兩項測試，分別為一分鐘仰臥起坐測試及無時限仰臥起坐測試。參加者會被安
排仰臥在墊子上，並由測試助理協助固定腳部。在一分鐘仰臥起坐測試進行時，參加者需在一
分鐘內，完成最多仰臥起坐次數；在無限時仰臥起坐測試進行時，參加者需盡力不間斷地完成
最多仰臥起坐次數。是次測試目的，是希望透過實驗，找出時間限制在仰臥起坐測試中的重要
性。
2. 存在風險及不適感覺
是次測試需要 貴子弟盡力做到最多仰臥起坐次數。因涉及肌力及肌耐力，參加者在完成測試
後，可能會感到腹肌部位有少許痛楚。所有不合理的動作將會立即被停止，把受傷風險盡量降
到最底。急救用品及有急救牌照的工作人員亦會從旁協助，如有任何意外亦可即時處理。
3. 參加者的責任
如參加者本身有任何肌肉受傷或其他不尋常的不適感覺，參加者有責任於測試前向測試工作人
員報告有關資料。如有任何其他藥物背景，參加者亦需於測試前向工作人員報告。
4. 參加測試將會得到的好處
參加是次測試，可以幫助參加者認識自己的腹肌耐力。
5. 詢問
如有任何關於測試項目內容的疑問，隨時歡迎提出。
6. 測試結果的運用
參加者所有個人資料及測試結果，只用於是次研究作統計及科學分析用途。為了保護參加者個
人私隱，如沒有參加者的書面同意，所有資料一概不會向任何人公開。
7. 參加者的意願
參加者參加是次測試，是出於自願性質的。如果參加者在測試前或測試期間感到不適，或不願
意進行測試，可在任何時候選擇退出測試，並不會有任何後果。
56
參加者責任聲明及家長同意聲明：
本人 ____________________ 身體健康狀況良好，適宜參加上述的仰臥起坐測試。
本人並未有任何疾病，適合參與是次測試，包括一分鐘仰臥起坐測試及無限時仰
臥起坐測試。如有疑問，本人會向醫生尋求指示。
在測試期間，如發生意外而導致任何事故，本人願承擔全部責任，主辦或協機構
並不需要負上任何法律責任。
此外，本人亦明白必須遵守是次測試的工作人員之安排。
確認日期：_________________ 參加者簽名：______________________
*未滿18歲的參加者，必須填妥以下部份：
家長/監護人姓名：__________________ 家長/監護人簽名：_________________
與參加者之關係：___________________ 日期：_____________________
