1. INFLUENCE OF FITNESS AND SEX ON
PERCEIVED EXERTION
DURING SUBMAXIMAL WALKING
Lovelyn Abbey
Thesis Presented in Partial Fulfillment
of the Requirements for the Degree
Master of Science

2. Acknowledgements
Dr. Pamela Swan
Dr. Shannon Ringenbach
Dr. Ann Sebren.
 Mike and Rene Abbey and rest of family
Ruth and Phil Lunn
 Theresa Seaquist, Jennifer Feula, and Caryl Webb
 Mike Miller

3. Introduction
 Many diseases such as cardiovascular disease,
osteoporosis, diabetes and cancer can be avoided or
managed with the addition of regular physical activity
(Franklin, 2000).
 American College of Sports Medicine, ACSM,
recommends that adults engage in 20-60 minutes of
moderate intensity exercise on most days of the week
(ACSM, 1998).
 However, less than 25% of people are regularly active
for this recommended length of time (Stevens, 1987).

4. Introduction
 Two determinants identified for increasing and
continuing physical activity. They are self efficacy and
enjoyment of the activity (Sallis, et al, 1989)
 Exercise intensity is directly related to both enjoyment
and self-efficacy (Sallis et al., 1989).
 The Rating of Perceived Exertion (RPE) Scale was
designed to make it easier for an individual to exercise
at the correct intensity (Dishman, 1993).
 RPE is defined as the ability to subjectively detect the
physiological sensations that result from exertion
(Robertson et al., 1997).

5. Borg RPE
 Developed by Gunner Borg
 Validated with many populations
 This 15-point scale ranges from 6 to 20 with each
number associated with word descriptions of the
intensity level.
 For instance, the number 7 is followed by a
description of extremely light whereas; the number
19 is followed by the description extremely hard
(O’Sullivan, 1984).

6. Borg RPE
6 No exertion at all
7 extremely light
8
9 Very light
10
11 Light
12
13 Somewhat hard
14
15 Hard (heavy)
16
17 very, very hard
19 extremely hard
20 Maximal exertion

7. Omni RPE
 A limitation of the Borg scale is that the numbers, which are related
to abstract words, are often difficult conceptually for novice
exercisers or children to gauge their level of intensity.
 To help solve this problem the Omni RPE Scale was developed
(Robertson, 2000).
 The Omni RPE Scale uses pictures associated with numbers and
words to help participants visualize their exertion level more
concretely.
 The Omni RPE scale consists of different pictures of progressively
incremented intensities on the cycle ergometer or treadmill
(Robertson et al., 2004; Pfeiffer, Pivarnik, Womack, Reeves, &
Malina, 2002).

8. Omni RPE

9. Purpose
 Examine the differences between the Borg RPE and the
Omni RPE scales during 60 minutes of submaximal
walking in individuals of low/average and high fitness
levels.
Questions
 What are the differences between the Borg RPE and
Omni RPE values during 60 minutes of walking at 50%
VO2 max in men and women with different fitness
levels?
 What is the relationship between the Borg and Omni
RPE scales during submaximal walking in men and
women with different fitness levels?

10. Hypothesis
 There will be no significant differences between fitness
groups in the Borg RPE scale and the Omni RPE
scale during steady state walking at 50% VO2
maximal exercise in men or women.
 There will be a significant positive correlation between
the Borg and Omni RPE scales.

11. Definitions
 VO2 Max (Maximal oxygen consumption): The
maximal rate at which the body can consume oxygen.
It is a measure of the ability to pick up oxygen at the
lungs and then distribute it to the working muscles
during physical activity/ exercise.
Fitness Categories based on ACSM Criterion for age/sex
 High Fit Males: VO2 >39 ml.kg-1.min-1
 High Fit Females: VO2 >34 ml.kg-1.min-1
 Low/Ave Fit Males: VO2 max < 38 ml.kg-1.min-1
 Low/Ave Fit Females: VO2 max < 33 ml.kg-1.min-1

12. Methods
Subject selection
 ~ 80 men and women between ages of 18-45
 Screened for health history
 Signed a written consent
 Free from cardiovascular disease, cancer,
diabetes, < 45 years of age and are at low health
risk
 IRB approved experimental procedures for
human subject experimentation at ASU

13. Methods
Experimental Design
 Cross sectional analysis of the
differences between two RPE scales
(Borg and Omni) between men and
women of different fitness levels during
60 minutes of submaximal treadmill
walking.

14. Methods
Procedures (2 Visits to Lab)
First visit
Read and signed consent form and health
history questionnaire
All anthropometric data collected
 Height, weight, body fat (BODPOD)
Bruce maximal graded exercise test (GXT)
conducted

15. Methods
Visit 2:
5-7 days later, participant returned
Treadmill speed and grade adjusted during
first 10 minutes to verify participants stayed
at 50 to 55 percent of VO2 max
Individual’s perception of exercise
(RPE) collected every 10 minutes
Both Borg and Omni randomly shown
VO2 collected by using indirect calorimetry
and HR was collected with the polar
monitor- every 10 minutes

16. Statistical Analysis
 Data were analyzed using SPSS version 16.0.
 Mean descriptive data were calculated for men,
women and the combined group.
 Repeated measures ANOVA was used to analyze the
differences in the two RPE scales over time (six time
periods) between the two fitness groups for each sex.
 Pearson correlation was used to determine the
relationships between RPE scales.
 A p value of < 0.05 was used to determine statistical
significance.

17. Statistics
 The Borg and Omni scales were converted to
standardized z-scores so they could be compared.
 Five fitness groups were identified based on age and
sex VO2 max data using the aerobic capacity standards
from the ACSM(ACSM, 1997)
 However, the “low” fitness group had 0 participants
and the “fair” group only had 6 people, so the “low”
and “fair” groups were combined with the “average”
group (N=19) to create a group called “low/average”
for a total of 25 people.
 In order to make the fitness categories as distinct as
possible, the people in the “good” fitness group (N=
34) were eliminated such that only two fitness groups
remained (i.e., “low/average”, N = 25; and “high” group, N =
20) (Total of 45 people).

18. Results
Table 1 indicates that the males were
significantly heavier, taller and had
significantly (p < 0.05) higher VO2 and
heart rate max values compared to the
females.
However, no sig differences in
submaximal HR or % of VO2 during the
walk

19. Descriptive
Data
Variable Male Female Total
N = 37 N=42 N = 79
Mean SD Mean SD Mean SD
Age 29.0 7.7 32.1 7.6 30.6 7.7
Weight (kg) 81.8 12.4 62.8* 10.9 71.7 15.0
Height (cm) 179.5 6.2 169.2* 7.3 172.5 8.5
BMI (kg/M2
) 25.4 3.5 22.0* 3.5 23.9 4.2
Percent fat 18.5 5.7 27.0* 7.2 23.0 7.7
VO2 max 47.8 8.4 37.3* 7.6 42.2 9.5
(ml
.
kg
-1.
min
-1
)
HR max 187.4 8.6 181.6* 7.6 184.3 8.6
(bpm)
VO2 submax 24.0 4.0 18.8* 3.9 21.2 4.7
(ml
.
kg
-1.
min
-1
)
HR submax 122.5 11.2 123.3 29.3 122.9 22.5
(bpm)
% VO2 max 50.0 0.2 50.0 0.2 50.0 0.2

20. Results
 Table 2 and 3 indicate the RPE scale data. Table 2 is the
raw scores over time and Table 3 are the standardized
scores compared.
 There were no significant differences (p > 0.05) in the
non-standardized Borg or Omni RPE scores for any time
period when compared between sexes
 After standardizing the RPE values to z-scores, there
were no significant differences between the Borg and
Omni scales in the overall 60 minute mean values and
same with standardized Borg and Omni RPE Scales over
time between the sexes

21. RPE Scales
by Time
Variable Male Female Total
N = 37 N=42 N = 79
Mean SD Mean SD Mean SD
Borg 10 min 9.5 1.8 9.9 1.8 10.0 1.8
Omni 10 min 2.7 1.4 3.0 1.4 3.1 1.4
Borg 20 min 9.8 1.7 10.5 1.9 10.6 1.8
Omni 20 min 3.3 1.2 3.7 1.5 3.7 1.4
Borg 30 min 10.1 1.7 11.0 1.8 11.1 1.7
Omni 30 min 3.5 1.3 4.0 1.5 4.1 1.5
Borg 40 min 10.1 1.8 11.1 1.7 11.3 1.8
Omni 40 min 3.8 1.4 4.0 1.5 4.2 1.6
Borg 50 min 10.2 1.9 11.2 1.9 11.4 1.9
Omni 50 min 3.7 1.4 4.1 1.5 4.2 1.5
Borg 60 min 10.3 1.8 11.1 1.8 11.0 1.8
Omni 60 min 3.8 1.6 4.1 1.4 4.0 1.5

22. Comparison of
Standardized RPE
Scales
Variable Male Female Total
N =37 N=42 N = 79
Mean SD Mean SD Mean SD
Borg 10 min -0.038 1.10 -0.113 1.04 -0.085 1.05
Omni 10 min -0.001 1.04 -0.150 1.06 -0.095 1.04
Borg 20 min -0.009 0.99 -0.122 1.10 -0.075 1.06
Omni 20 min 0.000 1.06 -0.100 1.10 -0.064 1.08
Borg 30 min 0.065 1.00 -0.122 1.07 -0.054 1.04
Omni 30 min 0.037 1.06 -0.101 1.10 -0.051 1.08
Borg 40 min 0.157 1.11 -0.137 0.98 -0.032 1.03
Omni 40 min 0.189 1.11 -0.150 1.03 -0.029 1.06
Borg 50 min 0.196 1.08 -0.120 1.04 -0.004 1.06
Omni 50 min 0.132 1.12 -0.057 1.03 0.013 1.06
Borg 60 min 0.199 1.21 -0.134 0.96 -0.015 1.05
Omni 60 min 0.113 1.13 -0.087 0.99 -0.016 1.03
Borg overall mean 0.095 0.95 -0.122 0.93 -0.044 0.94
Omni overall mean 0.076 0.98 -0.105 0.96 -0.040 0.97

23. Results
Table 4 indicates the Pearson
correlation Coefficients between the
variables.
There was a significant (p < 0.01)
correlation between the mean Borg and
Omni values (r = 0.897) over the 60
minutes of walking

24. Pearson Correlation
Borg Omni zBorg zOmni HR VO2 % Max
Borg 1
Omni 0.897** 1
zBorg 0.896** 1.000** 1
zOmni 1.000** .898** .897** 1
HR -0.030 -0.100 -0.099 -0.030 1
VO2 0.138 0.137 0.140 0.139 -0.056 1
% Max 0.200 0.193 0.195 0.202 0.102 0.002 0.103

25. Results
 Figure 1 and 2 are a comparison of the RPE scales
between the sexes. Although the graphs indicate that
the males were primarily in the positive values and the
females were in the negative values there was no
statistically significant differences over time.
 This is probably because of fitness differences
between the sexes.

26. Comparison of Borg RPE by sex
(Male N = 37; Female N = 42)

27. Comparison of Omni RPE by sex
(Male N = 37; Female N = 42)

28. Results
 Figures 3 -4 compare the Borg and Omni
scales between fitness groups.
 The “low/average” group started sig lower than
the high group and increased their RPE with
time. In contrast the “high” fitness group
gradually reported lower RPE with time.
 At about 40-50 minutes both groups reported
the same RPE values.
 These graphs indicate a significant time by
fitness group interaction (p = 0.03).

29. Comparison of Borg RPE scales by fitness group
(Low N = 25; High N= 20)

30. Comparison of Omni RPE scales by fitness group
(Low N= 25; High N = 20).

31. Figures 5 and 6 indicate that each
fitness group reacted the same to the
walking bout regardless of RPE scale.
Figure 5 indicates the Low/average
group response
Figure 6 indicates the High group
response.

32. Comparison of RPE scales in low fitness group (N= 25)

33. Comparison of RPE Scales in high fitness group (N = 20)

34. Discussion
No overall differences in Borg and Omni
values for the 60 minutes of walking
regardless of fitness level.
In addition, the two scales were highly
correlated.
Thus, both the first and second
hypothesis were accepted.

35. Discussion
 However, there was a significant time by fitness
group interaction.
 Figures 3 and 4 illustrate this interesting finding.
 The low/average group perceived the beginning
of exercise as fairly easy compared to the high
fit group and then as time progressed their
values increased such that they ended up higher
than the high fit group.
 In contrast, the perception of effort for the high fit
group which started high gradually decreased
with time.

36. Discussion
Thus, there is no indication that the Borg
or the Omni scales were different
between groups… however, there was a
difference between the perception of
effort in different fitness groups over
time.

37. Discussion
Explanation:
 Everyone walked on the treadmill at 50% of their max.
BUT, in the high fit people (mostly the men), to meet
the required VO2 intensity, the treadmill speed could not
be kept to a walking pace without greatly increasing the
grade.
 Thus, the most highly fit men were walking very fast up
a fairly steep incline.
 This type of exercise was unnatural to the participants. In other
words, although they kept their relative intensity at 50% of their
maximal VO2 they had to use a much greater effort to “push”
themselves up a hill for 60 minutes.
 It was clearly very strenuous especially on their legs.

38. Discussion
 Over time the high fit men gradually adapted to the
discomfort associated with the speed and grade of the
treadmill and their RPE assessment gradually reduced.
 The lower fit individuals reported the values as pretty
easy when they began.
 However, as time went on the lower fit group started to
describe their effort as gradually harder.
 Although their actual HR, VO2 intensity or the speed of
the treadmill was not changed during the 60 minute
bout, the lower fit group clearly indicated that their
exertion increased.

39. Discussion
These findings were even more pronounced when
the data were further analyzed by sex, however
the disproportionate and small numbers of each
sex in the fitness groups make the data suspect.
In the males (low/average N = 4; high fitness N =
14), a significant interaction (p = 0.042) was
found between time x scale x fitness group
whereas in the females (low/average N = 21;
high fitness N = 6) this trend only approached
significance p = 0.07.

40. Summary
 The Borg and Omni RPE scale have a high
correlation to each other during 60 minutes of
submaximal walking.
 Both scales were sensitive to differences in
reported exertion between low/average fit and
high fit men and women.
 Therefore, both the Borg and Omni scales are
appropriate for use in individuals with different
fitness levels.

41. Summary
However, although the two fitness
groups in this study were distinctly
different in their level of VO2 for age
category, the low/average fitness group
cannot really be considered typical for
low fit individuals.
Unknown what results would be with
really low fit individuals

42. Conclusion
 It is hoped that the results from this study will be
helpful to exercise professionals as they try to
motivate individuals to exercise at healthful and
enjoyable levels.
 Understanding that RPE can be used successfully for
individuals to regulate their intensity during exercise
will help the personal trainer work with their clients to
monitor themselves during exertion.
 It is hoped that with practice either RPE scale can be
used to help prevent injuries and add more pleasure
and motivation during exercise.

43. Thank You
Questions??

44. Fitness Categories Males
Age (yrs) LOW FAIR AVERAGE GOOD HIGH
20-29 <25 25-33 34-42 43-52 53+
30-39 <23 23-30 31-38 39-48 49+
40-49 <20 20-26 27-35 36-44 45+
50-59 <18 18-24 25-33 34-42 43+
60-69 <16 16-22 23-30 31-40 41+

45. Fitness Categories Females
Age (yrs) LOW FAIR AVERAGE GOOD HIGH
20-29 <24 24-30 31-37 38-48 49+
30-39 <20 20-27 28-33 34-44 45+
40-49 <17 17-23 24-30 31-41 42+
50-59 <15 15-20 21-27 28-37 38+
60-69 <13 13-17 18-23 24-34 35+