THE VALIDITY OF PREDICTION OF 1RM USING

RATINGS OF PERCEIVED EXERTION

BY

WONG CHUN KIT

07015704

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 2010

 

HONG KONG BAPTIST UNIVERSITY

23rd April, 2010

We hereby recommend that the Honours Project by Mr. Wong

Chun Kit entitled “The Validity of Prediction of 1RM Using

Ratings of Perceived Exertion” 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, Tom Dr. Louie Hung Tak, Lobo

Chief Adviser Second Reader

 

 

DECLARATION

I hereby declare that this honours project “The Validity

of Prediction of 1RM Using Ratings of Perceived Exertion”

represents my own work and had not been previously submitted

to this or other institution for a degree, diploma or other

qualification. Citations from the other authors were listed

in the references.

 

 

 

 

 

________________________ Wong Chun Kit

 

 

 23rd April, 2010

 

 

ACKNOWLEDGEMENTS

First of all, I would like to express my deepest gratitude

to my chief advisor, Dr. Tong Kwok Keung,Tom, 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. Louie Hung Tak, Lobo, to his effort on

this study.

Finally, special thanks must be given to all the subjects,

who are the students majoring in physical education and

recreation management from Hong Kong Baptist University, for

their participation in this study.

__________________________________

Wong Chun Kit

Department of Physical Education

Hong Kong Baptist University

Date: 23rd April, 2010

 

ABSTRACT

This study was designed to examine the validity of predicting

1RM using the Borg 6-20 ratings of perceived exertion (RPE)

scale from submaximal loads. Thirteen male and eleven female

participants who aged from 19 to 25 participate in this study.

Vertical chest press and leg press exercise were performed

for two times. Each participant was required to wear a

blindfold while lifting and all he RPE values were recorded.

Paired-Sample t test and Pearson Product Moment Coefficient

of Correlation were used and the significant level of 0.05

was set. The result indicated that there was a significant

positive relationship between the measured and predicted 1RM

loads for both upper(r=0.97, p0.05) were

insignificant. These results showed that submaxiaml ratings

of perceived exertion could be used to provide reasonably

accurate estimates of 1RM in young and active individuals.

 

TABLE OF CONTENTS

CHAPTER PAGE

1 INTRODUCTION............................. 1

Statement of Problem..................... 3

Significance of the Study................ 4

2 REVIEW OF LITERATURE...................... 6

Importance of Muscular Fitness........... 6

Factors Affecting Individual’s Muscular

Strength................................

8

Problems Associated with Direct Measure of

1RM Strength............................

9

Methods of Predicting 1RM Strength........ 12

Previous Studies on RPE and 1RM Strength... 14

Summary................................. 16

Research Hypotheses..................... 16

3 METHOD................................... 18

Subjects................................ 18

Research Design......................... 18

Testing Procedures...................... 21

Statistical Analysis................... 24

 

Definition of Terms.................... 27

Delimitations......................... 28

Limitation............................ 28

4 ANALYSIS OF DATA.......................... 30

Physical Characteristics................ 30

Background of Sports Participation....... 31

Vertical Chest Press..................... 32

Leg Press............................... 37

Discussions............................. 42

5 SUMMARY AND CONCLUSIONS................... 49

Summary of Results....................... 49

Conclusion.............................. 51

Recommendations for Further Study........ 52

REFERENCES............................... 53

APPENDIX................................. 58

A. Consent Form to Students............... 58

B. Data Recording Form................... 59

 

 

LIST OF TABLES

TABLE PAGE

1 The measured and predicted 1 RM loadings of each

subject for the vertical chest press

exercise(N=24)...............................

32

2 The sub-maximal loadings and related RPE scores

for the vertical chest press exercise(N=24)....

33

3 The group mean and standard deviation of

measured and predicted 1RM loading of vertical

chest press(N=24)............................

34

4 Pearson’s Correlation Test between the measured

and the predicted 1RM loading of vertical chest

press(N=24)..................................

35

5 The measured and predicted 1 RM loadings of each

subject for the leg press exercise(N=24).......

37

6 The sub-maximal loadings and related RPE scores

for the leg press exercise(N=24)...............

38

7 The group mean and standard deviation of measured

and predicted 1RM loading of leg press(N=24)....

39

8 Pearson’s Correlation Test between the measured

1RM and the predicted 1RM loading of leg press

(N=24).......................................

40

 

LIST OF FIGURES

FIGURE PAGE

1 The relationship between the measured and

predicted 1RM loading of vertical chest

press(N=24).................................

36

2 The relationship between the measured and

predicted 1RM loading of leg press............

41

 

 

1

Chapter 1

INTRODUCTION

Muscular strength is one of the health-related fitness

components (ACSM, 2003). Moreover, it is also an important

factor which affecting the performance of athletes. A fitness

routine should always consist of resistance training. For

beginners, it was necessary for them to assess their muscular

strength before prescribing a strength training program

(Adadie, Altorfer & Schuler, 1999). Among different ways in

assessing muscular strength, the One-Repetition Maximum test

(1RM) was regarded as a popular one (Niewiadomski et al., 2008).

In fact, instructor, coaches and physicians often used the

percentage of an individual’s 1RM to calculate and prescribe

the resistance training intensity (Pereira & Gomes, 2003).

However, the safety of the 1RM test had been questioned.

High muscular, bone and ligament stress with the risk of

serious muscular injury might result especially for those

individuals who were new to maximal load-bearing activity

 

2

(Braith, Graves, Leggett & Pollock, 1993). Moreover, Eston

(2009) suggested that high stress with the risk of muscular

injury or cardiovascular event might incur to those new to

maximal load-bearing activity. Besides, test-induced muscle

soreness and possible muscular injury might be created in

lifting maximal weight for the previously untrained

individuals (Adadie et al., 1999). What is more, the time

needed to prepare for and perform the 1RM and the risk of

handling heavy weights could be concerns of weight training

instructors and practicing lifter when measuring the 1RM

(LeSuer, McCormick, Mayhew, Wasserstei & Arnold, 1997). In

addition, Eston and Evans (2009) suggested that the direct

assessment of a 1RM was time consuming and unsafe for beginners.

Therefore, it was necessary to explore a simple, safe and

accurate procedure for estimating the 1RM.

Cafarelli (1982) reported that the perception of effort

was highly correlated with the degree of muscular activation.

On the other hand, the ratings of perceived exertion (RPE)

 

3

had been shown to be a valid and reliable estimate to high-

and low-intensity exercise (Gearhart et al., 2002),

high-volume weight training (Pierce, Rozenek & Stone, 1993),

the intensity of contraction between men and women (Pincivero,

Coelho & Campy, 2004) as well as for describing differences

in neuromuscular activation (Pincivero & Gear, 2000). Thus,

it was expected that the RPE was an effective assessment tool

for predicting muscular strength. In fact, with the

consideration of the finding that the degree of muscular

activation was highly correlated with the perception of effort

(Cafarelli, 1982) as well as given the health and safety

advantages of using submaximal repetitions to predict 1RM,

a similar study had been done in foreign country previously

with the hope of exploring the utility of the ratings of

perceived exertion as a holistic assessment tool for

predicting muscular strength (Eston & Evans, 2009).

Statement of Problem

The purpose of this study was to examine the validity of

 

4

predicting 1RM using the Borg 6-20 ratings of perceived

exertion (RPE) scale from submaximal loads in University

physical education major students of Hong Kong. It was hope

that a reasonably accurate, safe and time saving way to predict

1RM muscular strength would be found.

Significance of the Study

A similar study in foreign country had successfully shown

the validity of submaximal ratings of perceived exertion to

predict one repetition maximum. However, there was a lack of

studies that focusing on the Hong Kong Chinese individuals.

This study provided data on the topic and helped to enhance

the generalization of this muscular strength assessment

protocol.

To calculate and prescribe intensity for weight training,

the percentage of an individual’s 1RM was commonly used

(LeSuer et al., 1997). Exploring a simple, safe and accurate

procedure for estimating the 1RM was undoubtedly necessary.

Thus, the result of this study would be beneficial to strength

 

5

and conditioning specialists, sports medicine physicians,

athletic trainers as well as weight trainers.

 

6

Chapter 2

REVIEW OF LITERATURE

The review of literature of the study was focused on five

aspects: (a) importance of muscular fitness; (b) factors

affecting individual’s muscular strength; (c) problems

associated with direct measure of 1RM strength; (d) methods

of predicting 1RM strength; (e) previous studies on RPE and

1RM strength; and (f) summary.

Importance of Muscular Fitness

Health-related fitness was important for staying healthy

(ACSM, 2003). Generally, health-related fitness consisted of

four components including muscular fitness, aerobic fitness,

flexibility and body composition according to ACSM (2003).

Muscular fitness referred to the strength and endurance of

muscles, which were the ability to of muscle to exert force

and to continue to perform successive exertions or many

repetitions (ACSM, 2006). In the daily life, we always needed

strength to manipulate and move our body and the object around

 

7

us. On the other hand, we would like to have enough endurance

to position or hold the items. Thus, we could see that muscular

fitness was important to us.

ACSM (2006) stated that good muscular strength had many

benefits such as improving or maintaining bone mass, glucose

tolerance, fat free mass and resting metabolic rate etc.

Moreover, in order to do more work, protecting the joints from

injury and helping us to make our bones stronger, stronger

muscles were needed (McCormack Brown, Thomas & Kotecki., 2002).

According to Hazeldine (1990), research and experience over

the years had shown that effective performance in many sports

was closely related to high level of strength. What is more,

elite professional players and those at lower level were

distinguished by the scores on strength and power measures

especially in collision sports (Gamble, 2010). As a result,

the value of different strength trainings was well accepted

by sportsmen and those who wished to improve their general

fitness (Hazeldine, 1990). Therefore, muscular strength was

 

8

important to health as well as sports.

Factors Affecting Individual’s Muscular Strength

There were many factors that affecting individual’s

muscular strength. Lexell (1995) suggested that age was one

of the factors that affecting muscular strength. Skeletal

muscle mass lost with increasing age, while aging atrophy was

accompanied by a decrease in muscular strength. According to

Hurley (1995), muscular strength tended to reach the peak

between the second and third decades and remained the same

until about 45 to 50 years old. After that, the losing rate

was about 12% to 15% per decade until eighth decade. Moreover,

individual difference in muscle fiber type was also

contributed to different muscular strength. Lexell (1995)

stated that there was an inherent variability in the fiber

composition, which referred to the proportion of type I

(slow-twitch) and II (fast-twitch) fiber, in the human muscle.

On the hand, it was also found that type II fiber size was

reduced with increasing rate while the decrease in type I fiber

 

9

was much less. Loss of a specific type of fiber would occur

with increasing age thus affect the fiber type proportion

(Lexell, 1995). In addition, Fahey (2010) stated that genetic

factor was a significant determinant of strength as the number

of muscle fibers and fiber types within each muscle, body size,

bone length etc. are determined by genes. What is more,

difference in gender will also affect the muscular strength

(Fahey, 2010) due to the larger muscle mass of men than women.

More than this, males were found to have more testosterone

that promotes the growth of muscle tissue than women. As a

result, larger muscles were tended to be found in men. In

addition, muscles were activated faster by the nervous system

in male, thus they were tended to have more power.

Problems Associated with Direct Measure of 1RM Strength

Assessment of dynamic muscular strength could be done by

measuring the weight for one-repetition maximum (1RM) effort

when doing a resistance exercise (Cummings & Finn, 1998).

Although direct measurement was a popular way to determine

 

10

the 1RM strength, there were many disadvantages for such

method. Regarding the safety concern of 1RM protocol, high

muscular stress with the risk of muscular injury or

cardiovascular event might incur for those new to maximal

load-bearing activity (Eston, 2009). Nascimento et al. (2007)

stated that high muscular, bone and ligament stress that

triggering important metabolic alterations might result

during the performance of exertions with maximal workloads.

More than this, Abadie et al.(1999) suggested that potential

for test-induced muscle soreness and possible muscular injury

might be created in previously untrained individuals thus

making this type of assessment become contraindicated to them.

Moreover, it was reported that the direct measurement of 1RM

was time consuming and impractical for large group (Eston &

Evans, 2009). LeSuer et al.(1997) also stated that the time

needed to prepare for and perform the 1RM became one of the

concerns to weight training instructor as well as practicing

lifter. Besides, Pereira and Gomes (2003) stated that the

 

11

value of 1RM was likely to be over or underestimated since

1RM was hardly performed. Underestimating of the actual

strength of inexperienced individuals might occur since the

apprehension of lifting such heavy loads would compromise

their performance (Kim, Mayhew & Peterson, 2002). Furthermore,

Morales and Sobonya (1996) also suggested that preventing

individual from attaining maximum might result since 1RM test

induce fatigue. Additionally, the requirement of highly

specialized skill that involved a great deal of technique

could also be a concern of a 1RM lift (Brzycki, 1993). Finally,

unaccustomed insecurity while handling heavy loads,

inadequate spotting assistance as well as fear of failure with

the lift might make the 1RM test difficult for novice lifter

(Kravitz, Akalan, Nowicki & Kinzey, 2003). As a result, there

was a need for developing the methods that was simpler and

less injury-prone but still capable for estimating maximal

strength accurately (Materko, Neves & Santos, 2007).

 

12

Methods of Predicting 1RM Strength

Safety had become a major concern in measuring the 1RM

strength directly (Brzycki, 1993), especially for beginner.

In fact, apart from direct measure, there were many methods

which could be used to predict 1RM strength. Traditionally,

submaxiaml repetitions test was often used as a predictor of

1RM strength. Brzycki (1993) had found that the number of

repetitions would decrease when the maximal weight increase

in an almost linear fashion. In another words, there was a

direct relationship between repetitions-to-fatigue

(reps-to-fatigue) and the percentage of maximal load. This

nearly linear relationship between reps-to-fatigue (within

10 repetitions) and percentage of maximal load provided a

reasonably accurate prediction of 1RM strength by using

different prediction equation. It was found that the equations

were most accurately predicting the 1RM bench press, squat

and deadlift respectively (LeSuer et al.,1997). Abadie and

Wentworth (2000) stated that the prediction of 1RM by using

 

13

regression equation would be more accurate if the submaximal

weight lifted was closer to the weight lifted during the 1RM

assessment. Moreover, the anthropometric dimensions could

also be used to predict 1RM strength. Scanlan, Ballmann,

Mayhew and Lantz (1999) stated that structural dimensions

might be related to muscular strength. They had found that

arm often had the highest correlation with 1RM bench press

in many previous studies. Mayhew, Piper and Ware (1993) stated

that the predictive accuracy from structural dimensions would

be greater when fewer joints and muscle groups were involved

in a lift. It had been found that strength was related to muscle

when force was measured either isometrically or

isokinetically as indicated by previous study (Mayhew et al.,

1993). However, the accuracy of using the anthropometric

dimensions to predict 1RM strength wa varied with gender and

level of training of individual (Scanlan et al., 1999).

Besides, the validity of using submaxiaml RPEs to predict 1RM

was assessed in recent decade. Eston and Evans (2009)

 

14

discovered that the Borg 6-20 RPE Scale is valid in estimating

the 1RM strength in active men and women as there was no

significant difference between the 1RM loading predicted from

RPE 20 and measured 1RM. In addition, Gearhart et al. (2001)

suggested that it was valid for the current scaling

instructions used with the Borg 15-category scale during

resistance exercise. Thus, the result of these findings

supported that a reasonably accurate, safe and time-saving

way of estimating 1RM in active men and women could be provided

by submaximal RPEs.

Previous Studies on RPE and 1RM strength

Rating of perceived exertion (RPE) was closely related to

exercise. In fact, evaluating exercise tolerance and

prescribing exercise intensity had been done using the Borg

15-category scale of perceived exertion in clinical, sport

and wellness settings (Gearhart et al., 2001) in the past.

In recent years, the use the ratings of perceived exertion

(RPE) in resistance training had been assessed. Robertson et

 

15

al. (2003) expressed that the RPE for both male and female

performing concentric and eccentric resistance paradigms that

varied the total volume of weight lifted, percent of one

repetition maximum muscular action as well as rest periods

between separate sets and exercises had been assessed.

Recently, Eston (2009) had further confirmed the predictive

efficacy of the RPE. Eston and Evans (2009) had assessed the

validity if using submaxiaml RPEs to predict 1RM in young

adults by using the Borg 6 – 20 RPE Scale. It was found that

there was no significant difference between the 1RM predicted

from RPE 20 and measured 1RM. Thus, it was said that a

reasonably accurate, safe and time-saving way of estimating

1RM strength in young and active adults could be provided by

submaxiaml RPEs. On the other hand, Robertson et al. (2008)

had also found that the 1RM models were potentially applicable

when assessing large numbers of children in short time period

since the RPE predictors were practical and accurate measures.

 

16

Summary

As observed above, there was a need for discovering a simple,

time saving and accurate way to measure the 1RM strength.

Estimation of strength could be achieved by applying the

principle of using the relationship of submaximal RPE values

with the performance criterion of interest. From the studies

in foreign country, it had been proved that submaximal RPE

could be used to provide reasonably accurate prediction of

1RM in both active adults and children. Since no study in such

area had been done in Hong Kong yet, it was worthwhile for

us to do this study

Research Hypotheses

According to the above literatures reviewed, it was

hypothesized that:

1. There is a significant difference between the measured and

predicted 1RM loads for the vertical chess press exercise.

2. There is a significant difference between the

 

17

measured and predicted 1RM loads for the leg press exercise.

3. There is a significant correlation between the measured and

predicted 1RM for vertical chest press exercise.

4. There is a significant correlation between the measured and

predicted 1RM for leg press exercise.

 

18

Chapter 3

METHOD

The method of this study was divided into the following

sections: (a) subjects; (b) research design; (c) testing

procedures; and (d) statistical analysis.

Subjects

Thirteen male and eleven female undergraduate students

from Hong Kong Baptist University majoring in Physical

Education and Recreation management were invited to

participate in this study. Their age was between nineteen and

twenty five years old. They had active sport participation.

All the subjects were asked to sign on the consent forms after

knowing the purpose, benefits and risks of this study.

Research Design

To examine the validity of predicting 1RM load by using

the Borg 6-20 RPE scale, participants were required to

participate in two exercises (vertical chest press and leg

press) Totally, two trials were included for each exercise

 

19

in this investigation.

Orientation Trial

The aim of the orientation trial was to find out the 1RM

on two testing exercises, which were vertical chest press and

leg press, for each individual participant. All participants

received the coaching on safe, correct and experimentally

accepted weight lifting techniques required for this study

before the trial. The 1RM tests for both lifts were performed

according to guidelines from the National Strength and

Condition Association (NSCA certification commission, 2008).

Standardized instruction for the Borg 6 – 20 RPE scale (Borg,

1998) was given to the participants. They were asked to

verbally report the rating of perceived exertion from the Borg

6 – 20 Scale after each attempt until the maximal exertion

(a rating of 20) was reached.

Experimental Trial

Participants were required to perform the previous

exercises at sub-maximal intensities during the experimental

 

20

trial which occurred at least 48 hours after the orientation

trial. The order of exercises was counterbalanced with one

half of the group performing the leg press exercise before

the vertical chest press exercise, and vice versa. Four sets

of two repetitions on each exercise with each set performed

at an unknown pre-determined intensity (20, 40, 60 and 80

percent) were performed by the participants. The presenting

order of the four intensities was randomly chosen by the

investigator and not made apparent to the participant. Each

participant was required to wear a blindfold while lifting

in order to ensure there were blinded to the load and thus

unable to make a pre-determined judgment on perceived exertion

for that particular set.

The RPE was recorded after performing each set at the four

prescribed intensities. Participants were reminded to think

about the feelings of exertion in the active muscle group

during the concentric phase of the final repetition of each

set. The blindfold was removed immediately after the

 

21

participant relieved the weight. They were allowed to see and

verbally report the rating of perceived exertion from the Borg

6 – 20 Scale. Then, the participants were blindfolded again

and a different percentage of 1RM intensity was chosen by the

investigator randomly. The trials continued until four sets

were completed while the RPE values had been recorded for each

exercise.

Testing Procedures

In this study, all the subjects were invited to perform

vertical chest press and leg press in random sequences. Both

tests were conducted in the fitness room of Wai Hang Sports

Center in Hong Kong Baptist University. The following

guidelines with the reference of the National Strength and

Condition Association (NSCA certification commission, 2008)

would be used.

Vertical Chest Press

The participant performed this exercise sitting on the

seat of the machine and leaned back to place the body in a

 

22

five-point body-contact position. This included head,

shoulders, buttocks, left foot and right foot. It was made

clear to the participant that these points of contact must

remain throughout the lift in order to isolate the pectoris

major. The exercise utilized a closed and pronated grip with

both hands grasping the handles and it was performed in the

horizontal plane.

The movement began from pushing the handles forward to

full elbow extension. The participants first performed the

backward movement by allowing the handles to move toward the

body slowly and under control. Then, the participant

performed the forward movement by pushing the handles forward

while maintaining the same stationary five-point body-contact

position. The wrists were keeping stiff and continue to push

the handles until the elbows were fully extended but not

forcefully locked. The concentric phase last for two seconds

while the eccentric phase last for four seconds.

 

23

Leg Press

The leg press exercise was performed using the seated

leg press machine. First of all, sit inside the machine with

the head, back, hips and buttocks pressed evenly against their

respective pads. Adjust the back pad by moving it up and down

to allow the torso and legs to form approximately a 90-degree

angle at the hips when the feet were properly positioned in

the foot platform and the knees were fully extended. Placing

the feel with shoulder width on the foot platform with the

toes pointed slightly outward. Both feet must be positioned

in the same manner that same space should be seen between the

left foot and the left side of the platform as well as between

the right foot and the right side of the platform.

Grasped the handles throughout the test and

simultaneously extended the hips and knees to raise the foot

platform 1 to 2 inches (3 to 5 cm). Extend the hips and knees

to raise the foot platform to the starting position without

locking out the knees.

 

24

Begin the exercise with downward movement by flexing the

hips and knees slowly and under control while keeping the hips

and buttocks on the seat and the back flat against the back

pad. Continuous the downward movement phase until the heels

rise off the foot platform. Do not relax the legs and torso

at the bottom of the movement as well as bounce the foot

platform to spring it back up for the next repetition.

Then, perform the upward movement by extending the hips

and knees to push the foot platform up and under control while

the feet should remain flat on the platform. Continue to push

the foot platform up until the knees were fully extended but

not forcefully locked. Keep the hips and buttocks on the seat

and the back flat against the back pad. . The concentric phase

last for two seconds while the eccentric phase last for four

seconds.

Statistical Analysis

The purpose of the current study was to examine the

validity predicting 1RM load using the Borg 6-20 ratings of

 

25

perceived exertion (RPE) scale from submaximal loads. The

followings were the statistical (null) hypotheses of the

study:

1. There would be no significant difference between the

measured and predicted 1RM loads for the vertical chess

press exercise.

2. There would be no significant difference between the

measured and predicted 1RM loads for the leg press

exercise.

3. There would be no significant correlation between the

measured and predicted 1RM for the vertical chest press

exercise.

4. There would be no significant correlation between the

measured and predicted 1RM for the leg press exercise.

Analysis of data was done on subject who completed all

tests. Physical characteristics such as age, weight and height

of the subjects were recorded. Statistical data were analyzed

by Statistical Package for Social Science Version 15.0 (SPSS

 

26

15.0). Descriptive data, such as mean and standard deviation

were worked out and all data were described in mean ±SD. Pearson

Product Moment Coefficient of Correlation (r) was used to

examine the relationship between the measured and predict 1RM

strength by using RPEs. Moreover, the predicted and measured

1RM values for the vertical chest press and leg press were

compared for significant differences using Paired-Sample

t-tests. The 1RM predictions were calculated by entering

individual participant RPE values and load (kg) at each

intensity into a linear regression equation of

1RM = b x (RPE 20) + a and extrapolating to a theoretical 1RM

at RPE 20. The percentage of standard error of estimate (SEE)

was calculated as SEE% = SEE / mean 1RM x 100%. The predictive

accuracy was expressed as the percentage of measured 1RM that

could be predicted from measured RPE data for both muscle group:

(Predicted 1RM / Measured 1RM)x 100%. All above, an alpha level

of 0.05 was used for indicating statistical significance.

 

27

Definition of Terms

The following terms were operationally defined especially

for this study:

Ratings of Perceived Exertion (RPE)

According to Borg (1998), ratings of perceived exertion

refers to overall perceived exertion, which depends on many

factors including sensory cues and somatic symptoms,

emotional factors , rating behaviour etc. to integrated into

a kind of gestalt or configuration. Moreover, a measure of

perceived exertion is the degree of heaviness and strain

experienced in physical work as estimated according to a

specific rating method.

Muscular Strength

Muscular strength is defined as “the ability of muscle to

exert force” (ACSM, 2006, p.80).

One-Repetition Maximum (1RM)

According to ACSM (2006), one-repetition maximum is

referred to “the greatest resistance that can be moved through

 

28

the full range of motion in a controlled manner with good

posture” (ACSM, 2006, p.81).

Delimitations

The study was delimited to the followings:

1. The participants of this study were delimited to the

undergraduate students majoring in physical education and

recreation management.

2. 24 students were volunteered to participate in this study.

All of them were come from Hong Kong Baptist University.

3. This study consisted of one orientation and one

experimental sessions which were separated by at least 48

hours

4. The tests would be carried out in the fitness room of Wai

Hang Sports Center in Hong Kong Baptist University.

Limitations

1. The result of this study could not produce a good

generalization since the sample size is small (n=10).

2. The motivation of the subjects in performing the tests was

 

29

uncontrollable.

3. The physical activity pattern of the subjects between each

testing sessions could not be controlled.

4. The measures of this study were specific to the muscle group

and joint angle that involved in the two tests (one for each

upper and lower body) only. Thus, the utility of the result

in describing overall muscular strength was limited.

5. The physical lifestyle and the physical activity level of

the subjects might affect their performance

 

 

30

Chapter 4

ANALYSIS OF DATA

Thirteen male and eleven female students of Hong Kong

Baptist University were invited to participate in this study.

The purpose of this study was to examine the validity of

predicting 1RM using the Borg 6-20 ratings of perceived

exertion (RPE) scale from submaximal loads in University

physical education major students of Hong Kong. All subjects

engaged in one orientation trial and one experimental trial

in the study. This chapter was divided into two main sections,

the results and discussions

Results

Physical Characteristics

The physical characteristics including the age, body

height and weight of the subjects were recorded. The age of

the participants were ranged from 19 to 25 years old with the

mean of 22 ± 1.5 years. On the other hand, the mean body height

of the participants was 168.1 cm ± 9.2 cm with the range from

 

31

150 to 183 cm. For body weight, the range was from 44 to 71

kg with the mean of 57.3 kg ± 8.5 kg.

Sports Participation Background

The frequency of sport participation per week among the

participants marked. In this study, one sport participation

session was defined as participating in continuous physical

activities involving large muscle groups with the minimum of

30 minutes duration. In average, the subjects had 2.8 ± 1.7

sessions of sports participation each week with the range from

1 to 7 sessions.

 

32

Vertical Chest Press Exercise

The measured 1RM and predicted 1 RM loadings of each subject

for the vertical chest press exercise were shown in table 1.

Table 1

The measured and predicted 1 RM loadings of each subject for

the vertical chest press exercise (N=24)

Subject Measured 1RM (lbs) Predicted 1RM (lbs)

1 135 119

2 155 131

3 115 110

4 190 171

5 90 77

6 145 158

7 185 174

8 120 124

9 170 199

10 160 144

11 170 194

12 220 233

13 235 250

14 65 58

15 60 79

16 75 67

17 80 81

18 55 82

19 100 103

20 45 45

21 65 71

22 60 50

23 60 59

24 50 58

 

33

The sub-maximal loadings and related RPE scores for the

vertical chest press exercise were shown in table 2.

Table 2

The sub-maximal loadings and related RPE scores for the

vertical chest press exercise (N=24)

Subject 20%

of

1RM

load

RPE

of

20%

load

40%

of

1RM

load

RPE

of

40%

load

60%

of

1RM

load

RPE

of

60%

load

80%

of

1RM

load

RPE

of

80%

load

1 30 7 50 8 80 15 110 18

2 30 7 60 9 90 15 125 19

3 25 6 45 8 70 14 90 16

4 40 6 75 10 115 15 150 17

5 20 6 35 12 55 14 70 18

6 30 6 60 9 90 13 115 15

7 35 7 75 9 110 13 150 18

8 25 6 50 9 70 12 95 16

9 35 7 70 10 100 12 135 15

10 30 6 65 8 95 14 130 18

11 35 6 70 9 100 11 135 15

12 45 6 90 8 130 13 175 15

13 50 6 95 11 140 13 190 15

14 15 7 25 11 40 13 50 18

15 10 6 25 7 35 10 50 14

16 15 8 30 11 45 12 60 19

17 15 7 30 10 40 11 65 17

18 10 10 20 11 35 15 45 15

19 20 9 40 11 60 17 80 17

20 10 7 20 10 30 17 35 17

21 15 7 25 10 40 15 50 15

22 10 6 25 11 35 19 50 19

23 10 7 25 10 35 18 50 18

 

34

24 10 9 20 11 30 16 40 16

In this study, individual participant RPE values and load

(lbs) at each intensity were used to run the linear regression.

Then, the predicted 1RM would be calculated by entering the

result of the linear regression into a linear regression

equation of 1RM = (b x RPE 20)+a. For example, the predicted

1RM of subject 1 by using the equation above would be

(6.395 x 20) + (-9.244) = 118.656 lbs

The group mean and standard deviation of measured and

predicted 1RM of vertical chest press were shown in table 3.

Table 3

The group mean and standard deviation of measured and

predicted 1RM loading of vertical chest press (N=24)

Mean (lbs) SD mean (lbs)

Measured 1RM of Vertical

Chest Press

116.86 11.84

Predicted 1RM of Vertical

Chest Press

118.21 12.26

 

  The result of the paired-sample t test of the measured and

predicted 1RM for vertical chest press indicated that the

 

35

difference between the measured and predicted 1RM of vertical

chest press was insignificant (t=-0.44, p>0.05).Therefore,

the null hypothesis of there would be no significant

difference between the measured and predicted 1RM for the

vertical chess press exercise was accepted.

The result of the Pearson product moment coefficient of

correlation (r) between the measured and predicted 1RM for

vertical chest press was shown as follow:

Table 4

Pearson’s Correlation Test between the measured and the

predicted 1RM loading of vertical chest press (N=24)

r r² p

Correlation between measured and

predicted 1RM loading of vertical

chest press

0.97** 0.94 0.000

** Correlation is significant at the 0.01 level (2-tailed)

 

The relationship between the measured 1RM and the predicted

1RM weight of vertical chest press was shown in Figure 1.

 

 

36

Figure 1

The relationship between the measured and predicted 1RM

loading of vertical chest press (N=24)

It was found that there was a significant positive

relationship between the measured and predicted 1RM of

vertical chest press (r=0.97, p

 

37

Leg Press Exercise

The measured 1RM and predicted 1 RM loadings of each subject

for the leg press exercise were shown in table 5.

 Table 5

The measured and predicted 1 RM loadings of each subject for

the leg press exercise (N=24)

Subject Measured 1RM (lbs) Predicted 1RM (lbs)

1 355 304

2 345 277

3 260 260

4 340 314

5 205 194

6 365 317

7 365 391

8 385 434

9 390 321

10 305 370

11 350 276

12 400 427

13 370 392

14 220 187

15 235 228

16 185 158

17 240 254

18 160 295

19 260 248

20 190 173

21 200 199

22 180 170

23 220 209

24 165 231

 

38

The sub-maximal loadings and related RPE scores for the

leg press exercise were shown in table 6.

Table 6

The sub-maximal loadings and related RPE scores for the leg

press exercise (N=24)

Subject 20%

of

1RM

load

RPE

of

20%

load

40%

of

1RM

load

RPE

of

40%

load

60%

of

1RM

load

RPE

of

60%

load

80%

of

1RM

load

RPE

of

80%

load

1 70 6 140 7 210 15 285 18

2 70 6 140 7 210 17 275 18

3 50 6 105 10 155 12 210 17

4 70 6 135 10 205 12 270 18

5 40 6 80 9 125 11 165 18

6 75 6 145 9 220 15 290 18

7 75 7 145 8 220 10 290 16

8 75 6 155 8 230 12 310 15

9 80 7 155 11 235 16 310 19

10 60 6 120 8 185 12 245 14

11 70 6 140 8 210 17 280 19

12 80 6 160 8 240 11 320 16

13 75 6 150 8 220 11 295 16

14 45 7 90 8 130 15 175 19

15 50 6 95 10 140 13 190 17

16 35 6 75 10 110 16 150 18

17 50 6 95 9 145 11 190 16

18 30 9 65 11 95 12 130 13

19 50 7 105 9 155 11 210 18

20 40 6 75 9 115 13 150 18

21 40 7 80 8 120 12 160 17

22 35 7 70 10 110 15 145 17

23 45 6 90 8 130 13 175 17

 

39

24 35 6 65 8 100 9 130 13

By using the result of linear regression from individual

participant RPE values and load (lbs) at each intensity, the

predicted 1RM could be calculated by entering the result of

the linear regression into the linear regression equation of

1RM = (b x RPE 20)+a, which similar to vertical chests press

exercise. By using subject 1 as an example, the predicted 1RM

of leg press would be (14.976 x 20) + 4.024 = 303.544 lbs

The group mean and standard deviation of measured and

predicted 1RM of leg press were shown in table 7.

Table 7

The group mean and standard deviation of measured and

predicted 1RM loading of leg press (N=24)

Mean (lbs) SD mean (lbs)

Measured 1RM loading of

Leg Press

278.75 16.89

Predicted 1RM loading of

Leg Press

276.21 16.83

 

The result of the paired-sample t test of the measured and

predicted 1RM for leg press indicated that the difference

 

40

between the measured and predicted 1RM of vertical chest press

was insignificant (t=0.26, p>0.05).Therefore, the null

hypothesis of there would be no significant difference between

the measured and predicted 1RM for the leg press exercise was

accepted.

  The result of the Pearson product moment coefficient of

correlation (r) between the measured and predicted 1RM for

leg press was shown as follow:

Table 8

Pearson’s Correlation Test between the measured 1RM and the

predicted 1RM loading of leg press (N=24)

r r² p

Correlation between the measured

and predicted 1RM loading of leg

press

0.83** 0.69 0.000

** Correlation is significant at the 0.01 level (2-tailed)

The relationship between the measured 1RM and the predicted

1RM weight of leg press was shown in Figure 2

 

41

Figure 2

The relationship between the measured and predicted 1RM

loading of leg press (N=24)

It was found that there was a significant positive

relationship between the measured and predicted 1RM of leg

press (r=0.83, p

 

42

Discussions

The purpose of this study was to examine the validity of

predicting 1RM using the ratings of perceived exertion (RPE)

from submaximal loads in University physical education major

students of Hong Kong. The discussion part was divided into

four sections: (a) concurrent validity of predicting 1RM load

by using the Borg 6-20 RPE scale, (b) relationship between

measured and predicted 1RM using the Borg 6-20 RPE scale, (c)

relationship between perceptions of effort and degree of

muscular activation, and (d) major factors affecting use of

the Borg 6-20 RPE scale.

Concurrent Validity of Predicting 1RM load by using the

Borg 6-20 RPE Scale

In the present study, it was found that there was a

significant correlation between the measured and predicted

1RM load by using the Borg 6-20 RPE scale. The relationship

was strong for both upper (r = 0.97, p

 

43

of the measured and predicted 1RM load for upper body exercise

was 94% (r² = 0.94). In another words, the coefficient of

nondetermination was only 6% which implied a strong

correlation in between. On the other hand, the common variance

of the measured and predicted 1RM load for lower body exercise

was only 69% (r² = 0.69). Thus the coefficient of

nondetermination was 31% which was attributed to the factors

other than the peripheral perception of effort such as

psychological effect and difference in muscular activation

etc.

According to current study, it was found that there was

an insignificant result showed between the measured and

predicted 1RM load by using the Borg 6-20 RPE scale in the

paired-sample t-test for both upper (t = -0.44, p>0.05) and

lower (t = 0.26, p>0.05) body exercise. In another words, there

was an insignificant mean difference between the measured and

predicted 1RM load by using the Borg 6-20 RPE scale with the

mean difference of 1.35 lbs and 2.54 lbs. Moreover, the high

 

44

predictive accuracy for both exercise (101.14% for upper and

99.09% for lower body exercise) and relatively lower

percentage of standard error of estimate (13% and 17% for both

upper and lower body exercise respectively) implied that the

1RM values derived from the regression equation by using the

data from the Borg 6-20 RPE scale was valid.

Relationship between the Measured and Predicted 1RM using

the Borg 6-20 RPE Scale

From the previous studies, it was found that there was a

strong association between maximal strength and repetitions

to fatigue (Eston & Evans, 2009). Such finding indicated that

maximal strength was related to peripheral perception of

effort. Since the rating of perceived exertion (RPE) scale

was related to peripheral perception of effort, it was

believed that there was a relationship between the measured

and the predicted maximal weight by using the Borg 6-20 RPE

scale.

Until present, limited study had been conducted in

 

45

examining the validity of sub-maximal perceived exertion

ratings from the Borg 6-20 scale for predicting 1RM for upper

and lower body exercise. Eston and Evans (2009) stated that

there was no significant difference in the measured and

predicted 1RM load by using the Borg 6-20 RPE scale for both

upper and lower body exercise in undergraduate students. The

result of the present study had given a support to this finding,

thus providing an encouraging support from the efficacy of

using sub-maximal RPE values to predict the 1RM in both upper

and lower body muscle groups.

Relationship between Perceptions of Effort and Degree of

muscular activation

Gearhart et al. (2002) stated that higher exertional

perceptions would be resulted when greater force was generated

during skeletal muscle contraction with greater resistance

load. In previous study, it was found that all participants

were able to distinguish between sub-maximal loads even though

they were blinded to the load lifted and the order by which

 

46

the load would be lifted. In the design of current study,

submaximal loads to relative percentages (20%, 40%, 60% and

80%) of individual 1RM was altered in order to achieve the

muscle activation and stimuli strength varied with intensity.

In result, same finding had been stated in the current study

in which the average RPE values of 20%, 40%, 60% and 80% of

1RM load were progressively increase (7, 10, 13 and 17 for

upper and 6, 9, 13, 17 for lower body exercise) in both

exercise.

Such linear relationship between perceptions of effort and

degree of muscular activation had been explained in many

studies previously. Eston and Evans (2009) stated that it was

best explained on the basis of “feel forward” hypothesis,

which stated that the corollary discharges from the motor

cortex were concurrently sent to the somatosensory cortex as

well as the recipient muscle during a resistance movement

(Cafarelli, 1982). As a result, greater tension development

and increased motor unit recruitment and firing frequency

 

47

would be resulted with higher load (Gearhart et al., 2001).

Muscle activation and thus the stimuli strength was varied

with intensity through altering the sumbmaximal load to the

relative percentage (20%, 40%, 60% and 80%) of 1RM load in

the present study.

Major Factors Affecting Use of Rating of Perceived exertion

According to previous study, rating of perceived exertion

(RPE) was mainly affected by two factors, which were the local

factor and the central factor (Pandolf, 1982). Local factor

was related to sensation or feelings of strain from the

exercise muscle and / or joints, while central factor related

primarily to cardiopulmonary sensations. Cafarelli (1982)

suggested that perceived exertion was contingent in the degree

of muscular activation, which indicated that it varied

according to the length of the muscle for a given load during

both concentric and eccentric contraction. As a result, the

RPE was in fact depending on the joint position throughout

the range of movement. In the present study, it seemed that

 

48

the local factor was the major factor that affecting the

participants in giving the RPE value since the exercises used

(vertical chest press and leg press) were related to muscular

fitness. As a result, the sensation of muscle and or joint

seemed share a greater part of the variance in giving the RPE

value.

 

49

CHAPTER 5

SUMMARY AND CONCLUSIONS

Summary of Results

This study was designed to examine the validity of

predicting 1RM using the Borg 6-20 ratings of perceived

exertion (RPE) scale from submaximal loads in University

physical education major students of Hong Kong.

Thirteen male and eleven female undergraduate students

from Hong Kong Baptist University majoring in Physical

Education and Recreation Management were invited to

participate in this study. They performed the vertical chest

press and leg press exercise for two times. The first trial

was the orientation trial that finding the 1RM load for both

exercise by direct measurement. The second trial was the

experimental trial, in which four sets of two repetitions on

each exercise with each set performed at an unknown

pre-determined intensity (20, 40, 60 and 80 percent) were

performed by the participants. Each participant was required

 

50

to wear a blindfold while lifting in order to ensure there

were blinded to the load and thus unable to make a

pre-determined judgment on perceived exertion for that

particular set. The RPE values at each intensity were recorded,

and the collected data were analyzed by the Statistical

Package for the Social Science (SPSS) for window 15.0 version

computer program. Paired-Sample t test, Pearson Product

Moment Coefficient of Correlation and Simpler Linear

Regression were used, and the significant level of 0.05 was

set.

The results of this study were summarized as follows:

1. There was an insignificant difference between the measured

and predicted 1RM loads for the vertical chess press

exercise (t=-0.44, p>0.05)

2. There was an insignificant difference between the measured

and predicted 1RM loads for the leg press exercise (t=0.26,

p>0.05).

3. There was a significant positive relationship between the

 

51

measured and predicted 1RM loads for the vertical chess

press exercise (r=0.97, p

 

52

by using the Borg 6-20 RPE scale is insignificant. Moreover,

there is a significant relationship between the measured and

predicted 1RM values by using the Borg 6-20 RPE. Since

statistic in the present study prove that the result of finding

1RM load by using different methods do not have a significant

difference and correlated, it is conclude that the submaxiaml

ratings of perceived exertion from the Borg 6-20 scale for

predicting 1RM is valid.

Recommendations for Further Study

1. The sample size should be enlarged in order to obtain more

representatives.

2. The variety of the exercises used in the test should be

increase with the hope of getting a comprehensive result

with different muscle group

3. Different age group apart from teenagers can be studied to

enlarge the external validity of the study

4. Fitness level of the participants should be considered.

 

53

REFERECES

Abadie, B. R., Altorfer, G. l. & Schuler, P. R. (1999). Does

a regression equation to predict maximal strength in

untrained lifters remain valid when the subjects are

technique trained? Journal of Strength and Conditioning

Resarch, 13, 259-263.

Abadie, B. R., & Wentworth, M. C. (2000). Prediction of one

repetition maximal strength from a 5-10 repetition

submaximal strength test in college-aged females. Journal

of Exercise Physiology Online, 3(3). Retrieved from

http://faculty.css.edu/tboone2/asep/JEPonlineABADIE.ht

ml.

American College of Sports Medicine. (3rd Ed.). (2003). ACSM

fitness book. Champaign, IL : Human Kinetics.

American College of Sports Medicine. (7th Ed.). (2006). ACSM’s

guidelines for exercise testing and prescription.

Philadelphia PA: Lippincott Williams & Wilkins.

Borg, G. (1998). Borg's Perceived exertion and pain scales,

Champaign, IL: Human Kinetics.

Braith, R.W., Graves, J.E., Leggett, S. and Pollock, M.L.

(1993) Effect of training on the relationship between

maximal and submaximal strength. Medicine and Science in

Sports and Exercise 25, 132-138.

Brzycki, M. (1993). Strength testing predicting a one-rep max

from reps-to-fatigue. Journal of Physical Education,

Recreation and Dance 64, 88–90.

 

54

Cafarelli, E. (1982). Peripheral contributions to the

perception of effort.Medicine and Science in Sports and

Exercise 14, 382-389.

Cummings, B., & Finn, K. J. (1998). Estimation of a one

repetition maximum bench press for untrained women.

Journal of Strength and Conditioning Research 12, 262–265.

Eston, R. G. (2009). Perceived exertion: recent advances and

novel applications in children and adult. Journal of

Exercise Science and Fitness 7(2), S11–S17

Eston, R. G., & Evans, H. (2009, in press). The validity of

submaximal ratings of perceived exertion to predict one

repetition maximum. Journal of Sports Science and Medicine

8, 567-573.

Fahey, T. D. (2010). Basic weight training for men and women.

New York : McGraw-Hill Higher Education.

Gamble, P. (2010). Strength and conditioning for team sports :

sport-specific physical preparation for high performance.

Milton Park, Abingdon, Oxon ; New York, NY : Routledge.

Gearhart, R. F., Goss, F. L., Lagally, K. M., Jackicic, J.

M., Gallagher, J., & Robertson, R. J. (2001). Standardized

scaling procedures for rating of perceived exertion during

resistance exercise. Journal of Strength and Conditioning

Research 15, 320-325.

Gearhart, R. F., Goss, F. L., Lagally, K. M., Jackicic, J.

M., Gallagher, J., Gallagher, K. I., & Robertson, R. J.

(2002). Ratings of perceived exertion in active muscle

during high-intensity and low intensity resistance

exercise. Journal of Strength and Conditioning Research

16, 87-91.

 

55

Hazeldine, R. (1990). Strength training for sport. Ramsbury,

Marlborough, Wiltshire : Crowood Press.

Hurley, B. F. (1995). Age, gender and muscular strength. The

Journals of Gerontology: Series A: Biological sciences and

medical sciences 50A, 41-46.

Kim, P. S., Mayhew, J. L., & Peterson, D. F. (2002). A modified

YMCA bench press test as a predictor of 1 repetition maximal

bench press strength. Journal of Strength and Conditioning

Research 16, 440-445.

Kravitz, L., Akalan, C., Nowicki, K., & Kinzey, S. J. (2003).

Prediction of 1 repetition maximum in high-school power

lifters. Journal of Strength and Conditioning Research 17,

167-172.

LeSuer, D.A., McCormick, J. H., Wasserstein, R. L., & Arnold,

M. D. (1997). Theaccuracy of prediction equations for

estimating 1- RM performance in the bench press, squat and

deadlift. Journal of Strength and Conditioning Research

11, 211-213.

Lexell, J. (1995). Human aging, muscle mass, and fiber type

composition. The Journals of Gerontology: Series A:

Biological sciences and medical sciences 50A, 11-16.

Materko, W., Neves, C. E. B., & Santos, E. L. (2007). Preiction

model of a maximal repetition (1RM) based on male and female

anthropometrical characteristics. Rev Bras Med Esporte,

13 (1), 22e-24e

Mayhew, J. L., Piper, F. C., & Ware, J. S. (1993).

Anthropometric correlates with strength performance among

resistance trained athletes. Journal of Sports Medicine

and Physiscal Fitness 33, 159-165.

 

56

McCormack Brown, K. M., Thomas, D. Q., & Kotecki, J. E. (2002).

Physical activity and health : an interactive approach.

Sudbury, Mass.: Jones and Bartlett.

Morales, J., & Sobonya, S. (1996). Use of submaximal

repetition tests for predicting 1RM strength in class

athletes. Journal of Strength and Conditioning Research

10, 186-189.

Nascimento, M. A., Cyrino, E. S., Nakamura, F. Y., Romanzini,

M., Pianca, H. J. C., & Queiroga, M. R. (2007) Validation

of the Brzycki equation for estimation of the 1RM in the

bench press. Revista Brasileira de Medicina Esporte 13,

40-42.

Niewiadomski, W., Laskowska, D., Gasiorowaska, A., Cybulski,

G., Strasz, A., & Langfort, J. (2008) Determination and

Prediction of One Repetition Maximum (1RM): Safety

Considerations. Journal of Human Kinetics 19, 109-120.

NSCA Certification Commission. (2nd Ed.). (2008). Exercise

technique manual for resistance training. Champaign, IL:

Human Kinetics.

Pandolf, K. B. (1982). Differentiated ratings of perceived

exertion during physical exercise. Medicine and Science

in Sports and Exercise 14, 397-405

Pereira M. I. R., & Gomes P. S. C. (2003). Muscular strength

and endurance tests:reliability and prediction of one

repetition maximum—review and new evidence. Revista

Brasileira de Medicina Esporte 9, 336–346.

 

57

Pierce, K., Rozenek, R., & Stone, M. H. (1993) Effects of high

volume weight training on lactate, heart rate and perceived

exertion. Journal of Strength and Conditioning Research

7, 211-215.

Pincivero, D. M., & Gear, W. S. (2000). Quadriceps

activation and perceived exertion during a high intensity,

steady state contraction to failure. Muscle and Nerve 23,

514-520.

Pincivero, D. M., Coelho, A. J., & Campy, R. M. (2004). Gender

differences in perceived exertion during fatiguing knee

extensions. Medicine and Science in Sports and Exercise

36, 109-117.

Robertson, R. J., Fredric, L. G., Aaron, D. J., Gairola, A.,

Kowallis, R. A., Liu, Y., Randall, C. R., Tessmer, K. A.,

Schnorr, T. L., Schroeder, A. E., & White, B. (2008). One

repetition maximum prediction models for children using

the OMNI RPE Scale. Journal of Strength and Conditioning

Research 22, 196–201.

Robertson, R. J., Goss, F. L., Rutkowski, J., Lenz, B., Dixon,

C., Trimmer, J., Frazee, K., Dube, J., & Andreacci, J. (2003)

Concurrent validation of the OMNI perceived exertion scale

for resistance exercise. Medicine and Science in Sports

and Exercise 35, 333-341.

Scanlan, J. M., Ballmann, K. L., Mayhew, J. L., & Lantz, C.

D. (1999). Anthropometric dimensions to predict 1RM bench

press in untrained females. Journal of Sports Medicine and

Physical Fitness 39, 54-60.

 

 

 

58

APPENDIX A

Consent Form to Students

Explanation of the tests For muscle fitness testing, you lift weights for a number of repetitions using exercise machines. These tests assess the strength and endurance of the major muscle groups in the body. Moreover, maximum effort testing is needed.

Risks and discomforts There is a slight possibility of pulling a muscle or spraining a ligament during the muscle fitness and flexibility testing. In addition, you may experience muscle soreness 24 or 48 hours after testing. These risks can be minimized by performing warm-up exercises prior to taking the tests. If muscle soreness occurs, appropriate stretching exercises to relieve this soreness will be demonstrated.

Expected benefits from testing The test allows us to assess your physical working capacity and to appraise your physical fitness status. The results are used to prescribe a safe, sound exercise program for you. Records are kept strictly confidential unless you consent to release this information.

Inquiries Questions about the procedures used in the physical fitness test are encouraged. If you have any questions or need additional information, please ask us to explain further.

Freedom of Consent Your permission to perform these physical fitness tests is strictly voluntary. You are free to stop the tests at any point, if you so desire. _____________________________________________________________________ I have read this form carefully and I fully understand the test procedures that I will perform and the risks and discomforts. Knowing these risks and having had the opportunity to ask questions that have been answered to my satisfaction, I consent to participate in these tests. Date: _________________ Signature of patient: ____________________ Date: _________________ Signature of witness: ___________________ From Vivian H. Heyward, 2006. Advanced Fitness Assessment and Exercise Prescription, 5th ed.

(Champaign, IL: Human Kinetics).

 

59

APPENIDX B

Data Recording Form

One repetition maximum prediction models for university students

Data Recording Form Name: ___________________________________ Age: _____ Gender: _____ Height:______(cm) Weight:_____(kg) Frequency of sport participation per week: ____ (At least 30 minutes with continuous sport participation each session) Interest in sport: ____ (1 to 5 points in which 5 points indicate most interest)

 

60

Trial 1 (Accurate 1RM measure) Test 1 – Vertical Chest Press

No. of Attempt Result (lbs) RPE score 1 2 3 4 5 6

Test 2 – Leg Press

No. of Attempt Result (lbs) RPE score 1 2 3 4 5 6

Trial 2 (1RM prediction) Test 1 – Vertical Chest Press

No. of Attempt Percentage of 1RM Result (lbs) RPE score 1 2 3 4

Test 2– Leg Press

No. of Attempt Percentage of 1RM Result (lbs) RPE score 1 2 3 4