Primary Image

RehabMeasures Instrument

Borg Rating Scale of Perceived Exertion

Last Updated

Purpose

The Borg Scale is a tool to measure a person’s perception of their effort and exertion, breathlessness, and fatigue during physical work.

Link to Instrument

Instrument Details

Acronym RPE

Area of Assessment

Aerobic Capacity

Assessment Type

Patient Reported Outcomes

Administration Mode

Paper & Pencil

Cost

Free

Cost Description

There is a fee of up to $1,100 for large organizations that request use of the Borg RPE Scale.

Key Descriptions

  • A 15-point scale with verbal descriptors to standardize perceived exertion across tasks and individuals
  • Instructions for use:?
    1) Explain that the scale rates how hard a person is working
    2) Full 15-point scale ranges from 6 = no exertion at all to 20 = absolute maximum
    3) Modified 11-point scale ranges from 0 = nothing at all to 10 = very, very hard
    4) Effort is graded using numbers and/or words
  • Measures training intensity and outcomes for exercise - parallels physiological variables
  • Many suggest carrying afferent input to RPE, but there is no consensus about what their effects may be (Hampson et al. 2001)
  • Appropriate for any individual capable of exercising

Number of Items

11

15

Equipment Required

  • Printed copy of the Borg RPE Scale

Time to Administer

5 minutes

Required Training

No Training

Age Ranges

Adolescents

13 - 18

years

Adult

18 - 64

years

Older Adults

65 +

years

Instrument Reviewers

Initially reviewed by Gayatri Mathur, PT; updated by Jill Smiley, MPH; reviewed by Patricia Kluding, PhD, PT of the StrokEdge task force, Neurology Section, APTA in 2010; updated by Jacqueline Kendona, 2016; updated by Dorian Rose, PhD, PT of the StrokEdge II task force, Neurology Section, APTA in 2017; updated by University of Illinois at Chicago Master of Science in Occupational Therapy students Gina Mulanthara, Annie Lee, and Chelsea Ebersole in 2018.

ICF Domain

Body Function

Measurement Domain

Motor
General Health

Professional Association Recommendation

Recommendations for use of the instrument from the Neurology Section of the American Physical Therapy Association’s Stroke Taskforce (StrokEDGE), are listed below. These recommendations were developed by a panel of research and clinical experts using a modified Delphi process.

For detailed information about how recommendations were made, please visit:

Abbreviations:

HR

Highly Recommend

R

Recommend

LS / UR

Reasonable to use, but limited study in target group / Unable to Recommend

NR

Not Recommended

Recommendations for use based on acuity level of the patient:

 

Acute

(CVA < 2 months post)

Subacute

(CVA 2 to 6 months)

Chronic

(> 6 months)

StrokEDGE

NR

R

R

Recommendations based on level of care in which the assessment is taken:

 

Acute Care

Inpatient Rehabilitation

Skilled Nursing Facility

Outpatient

Rehabilitation

Home Health

StrokEDGE

NR

R

R

R

R

Recommendations for entry-level physical therapy education and use in research:

 

Students should learn to administer this tool? (Y/N)

Students should be exposed to tool? (Y/N)

Appropriate for use in intervention research studies? (Y/N)

Is additional research warranted for this tool (Y/N)

StrokEDGE

Yes

Yes

No

Yes

  • Recommended in the American Thoracic Society’s 2002 guidelines (Hommerding et al., 2010)

Considerations

  • Yields useful information about fatigue during an activity

  • Lacks established test-retest reliability and validity of physiologic measures

  • Lacks evidence as an outcome measure, substitute for other measures of endurance, or guide to exercise prescription in stroke populations

  • Established reliability and validity for monitoring and prescribing exercise intensity for a variety of populations, except for stroke

  • Useful measure of subjective perception of dyspnea after physical activity

  • To ensure safety and efficacy, be careful in the instruction and use of the RPE scales. A study of the RPE with cardiac rehabilitation patients found that 80% of those who exercised at a RPE of 11 to 13 (as prescribed) were in fact exercising at levels deemed to be unsafe (e.g. > 60% VO2R) (Joo, Brubaker, MacDougall, Saikin, Ross, & Whaley, 2004).

  • Pain might influence a patient’s score, so it should be noted when applicable. For example, note “Leg RPE with knee pain” (Borg, 1998).

  • There is a possible language barrier - around 5 to 10% of adults will have difficulty understanding the instructions which will affect their ability to respond to the Borg RPE scale (Borg, 1998).

  • It is essential to give the correct instructions in order to get accurate results. The Borg RPE instructions should not be shortened or modified (Borg, 1998).

  • Though the Borg RPE has been used in numerous international studies, few studies have completed the cross-cultural adaptation necessary to retain psychometric properties. Studies have been conducted in Germany, Taiwan, China, Switzerland, and Spain (Cabral et al., 2017).

  • Cross-cultural adaptations of the Borg RPE include Cantonese and Japanese versions (Leung, Leung & Chung, 2004; Onodera & Miyashita, 1976).

Non-Specific Patient Population

back to Populations

Standard Error of Measurement (SEM)

Well-trained Males:  (Doherty, Smith, Hughes, & Collins, 2001; n = 15; 30s of the subpraximal run for each test)

  • 30 seconds: SEM = 0.79 (0.49-1.16)

  • 60 seconds: SEM = 0.78 (0.50-1.12)

  • 90 seconds: SEM = 0.80 (0.51-0.99)

  • 120 seconds: SEM = 0.76 (0.47-0.93)

Male Rowers (Marriot & Lamb, 1996; n = 9; mean age = 28.6 (6.8) years)

  • Mean RPE scores were 7.6 (SEM 0.9) and 18.9 (SEM 0.3) for entire group (n = 9)

Adolescent Girls (Pfeiffer, Pivarnik, Womack, Reeves, & Malina, 2002; n = 57; mean age = 15.3 (1.5) years)

  • SEM for entire group: 1.24

Helsinki Participants (Scherr, Wolfarth, Christle, Pressler, Wagenpfeil, & Halle, 2012; n = 2,560; mean age = 24 (17-44) years; Helsinki, Finland participants)

  • Total cohort:

    • RPE at LT1 = 10.8 ± 1.8 (SEM = 0.04)

    • RPE at LT2 = 13.6 ± 1.8 (SEM = 0.04)

    • Fixed lactate thresholds of 3 and 4 mmol/L were 12.8 ± 2.1 (SEM = 0.06) and 14.1 ± 2.0 (SEM = 0.06)

Test/Retest Reliability

Frail older adults: (Mendelssohn et al., 2008)

  • HR & METs (ICC = 0.85-0.91)

Healthy Male Athletes (Lamb, Eston, & Corns, 1999; n = 16; mean age = 23.6 (5.1))

  • Excellent at Stages 1 - 4: (ICC = .82, .80, .77, .75)

Depression and Anxiety (Knapen et al., 2003)

  • Reliability coefficients for males (r = 0.42, p < 0.05) & (r = 0.82, p < 0.01)

  • Reliability coefficients for females (r = 0.48, p < 0.01) & (r = 0.58, p < 0.01)

Adolescent Girls (Pfeiffer et al., 2002)

  • Excellent: (ICC = .78)

Interrater/Intrarater Reliability

Interrater Reliability:

In Braille:

  • In Braille: (Buckley et al., 2000; n = 10; female mean age = 22 (7.6); male mean age = 27.3 (11.7))

    • Three trials of exercise bouts at RPEs 9, 11, and 13

      • Between Trial 1 (RPE 9) and 3 (RPE 13) (ICC = .43)

      • Between Trial 1 (RPE 9) and 2 (RPE 11) (ICC = .69)

      • Between Trial 2 (RPE 11) and 3 (RPE 13): (ICC = .88)

Adolescent females: (Pfeiffer et al., 2002)

  • Excellent: (ICC = 0.78)

Intrarater Reliability:

Physically Active Men and Women (Eston et al., 2006; n = 19; male mean age = 21.6 (0.8); female mean age = 21.4 (1.4))

  • Predicted VO2 max from RPE: (ICC = 0.66-0.95)

  • No gender differences

Healthy Men and Women: (Eston & Williams, 1988; n = 16; male mean age = 28.7 (12.5); female mean age = 31.8 (9.4))

  • Between trials (ICC > 0.83)

Criterion Validity (Predictive/Concurrent)

Concurrent validity:

Male Rowers (Marriot & Lamb, 1996)

  • Excellent: High Pearson correlation coefficients between HR and RPE (r = 0.95, p < 0.01) and Work Output and RPE (r = 0.96, p < 0.01) during the estimation trial. In addition, significant correlations (p < 0.01) were obtained between the estimation and production trials for HR (r = 0.82) and Work Output (r = 0.84). Post hoc analysis of variance revealed that the observed differences in mean HR were not significant (p > 0.05) at three of the five intensity levels (RPE 15, 17 and 19), but were at the two lowest RPE levels (11 and 13). Significant mean differences in Work Output were seen at all but RPE 17.

Young African-Americans (Karavatas & Tavakol, 2005; n = 12; mean age = 26.08 years)

  • Adequate: The overall correlation between RPE and HR was 0.58 (p < 0.01)

    • Excellent: Males (n = 6), r = 0.60; p < 0.01

    • Adequate: Females (n = 6), r = 0.56; p < 0.01

 

RPE Across the Lifespan: (Groslambert & Mahon, 2006; n = 1,865)

  • Poor: Correlation with HR in children 0-3 as children of this age are not able to rate their perceptions

  • Variable: Correlation with HR in children 3-7 years

  • Variable: Correlation with HR in children 8-12 years

  • Good to Excellent: Correlation with HR in children 13+ years similar to adults

  • No Significant Effect on Validity: With people ages 50-65, >65

 

Healthy Individuals: (Chen et al., 2002)

  • A meta-analysis of criterion-related validity between RPE and physiological measures in healthy individuals (mean age of subjects in studies was 32.7; range 9 to 75 years).

Range of mean validity coefficients with RPE:

Heart rate

Blood lactate

VO2max or VO2

Ventilation

Resp rate

0.47-0.61

0.42-0.69

0.31-0.76

0.53

0.67

  • Strongest relationships were noted in highly fit male participants at high (maximal) exertion.

 

Predictive validity

Pregnant Women: (O’Neill et al., 1992; Group 1 (Treadmill), n = 11; Group 2 (Bicycle), n = 12; Group 3 (Circuit-training), n = 24; Group 4 (Aerobics), n = 48; Group 5 (Aerobics), n = 29)

  • Excellent: HR during walking and cycling correlated significantly with RPE after delivery

    • Group 1 (Treadmill), r = 0.83, p < 0.01, n = 11

    • Group 2 (Bicycle), r = 0.74, p < 0.015, n = 12

  • Adequate: There was no significant correlation when the same subjects were tested in the second trimester (Group 1 (Treadmill), r = 0.45) and/or in the third trimester (Group 1 (Treadmill), r = 0.47; Group 2 (Bicycle), r = 0.51) (p > 0.05).

  • Poor: RPE and HR also failed to correlate in the pregnant women who participated in aerobics or circuit-training (p > 0.05)

    • Group 3 (Circuit-training), r = 0.39, n = 24

    • Group 4 (Aerobics), r = 0.27, n = 48

    • Group 5 (Aerobics), r = 0.35, n = 29

Helsinki Participants: (Scherr, Wolfarth, Christle, Pressler, Wagenpfeil, & Halle, 2012)

  • Excellent relationship between RPE and blood lactate: r = 0.84, p < 0.001

  • Excellent relationship between RPE and HR: r = 0.74, p < 0.001

  • Strong correlations indicate high predictive value of RPE for HR and blood lactate.

 

  • The RPE scale (with rating of 6 to 20) was developed so heart rate could be predicted by multiplying the RPE by 10 (Borg, 1982).

Construct Validity

Convergent validity

Elite Swimmers (Psycharakis, 2011; males, n = 9; females, n = 8; males mean age = 23.4 (2.1); females mean age = 20.5 (1.9); male mean height = 186.6 cm (6.0 cm); female height = 170.1 cm (3.8 cm); male body mass = 83.7 kg (6.6 kg); female body mass 60.9 kg (5.6 kg)

  • Excellent convergent validity of RPE at predicting %HRmax (r = 0.85)

  • Excellent convergent validity of RPE at predicting La (r = 0.82)

Video Game Players (Pollock et al., 2013; n = 13; mean age = 53.5 (5.4))

  • Adequate discriminant validity of RPE at predicting heart rate (r = 0.32)

Children and Adults (Gillach, Sallis, Buono, Patterson, & Nader, 1989; children, n = 283; adults, n = 295; children mean age = 11 (10-14); adults mean age = 36 (22-55))

  • Excellent validity for HR and RPE in children based on mean of individual correlations

    • Test 1, r = .92, p < .001

    • Test 2, r = .94, p < .001

  • Excellent validity for HR and RPE in adults based on mean of individual correlations

    • Test 1, r = .94, p < .001

    • Test 2, r = .95, p < .05

  • Excellent validity for HR and RPE in children based on simultaneous analysis of entire group

    • Test 1, r = .64, p < .001

    • Test 2, r = .65, p < .001

  • Excellent validity for HR and RPE in adults based on simultaneous analysis of entire group

    • Test 1, r = .63, p < .001

    • Test 2, r = .64, p < .001

Stroke

back to Populations

Test/Retest Reliability

Not reported in stroke, however, one study (Eng et al., 2002; n = 25; 4.4 ± 3.0 yrs) assessed RPE in people with stroke at minute 6 during a 6-minute walk test and a 12-minute walk test in the same subjects, with almost identical mean values (11.6 and 11.7) for the 2 assessments, as would be expected if test-retest reliability was high.

Criterion Validity (Predictive/Concurrent)

(Eng et al., 2002; n = 25; 4.4 ± 3.0 yrs)

  • RPE poorly correlated with 6 MWT and 12 MWT distance in people with stroke. (r = -0.10 and -0.06 respectively)

  • In stroke, predicted HR based on RPE was significantly higher than the actual HR during 6 minute and 12 minute walk tests, and predicted and actual HR were not correlated

(Tseng et al., 2010; n = 21; 4.1 ± 3.5 yrs)

  • Strong correlation between RPE and ratings of exertion fatigue on a visual analog scale following exercise (r = 0.802, p = 0.00) in people with stroke.

Content Validity

Post-Stroke: (Sage et al., 2013. 37 patients post-stroke (14.5 ± 10.2 days post-stroke))

  • Respiratory gas exchange was monitored for analysis of VO2 while completing a graded maximal exercise test, while HR and RPE (Borg CR10 Scale) were measured at the end of each minute. 76.2%, 69.0%, and 38.9% of participants fell into the expected RPE range at each intensity. RPE appears to be a reasonable indicator of exercise intensity after stroke at moderate (60%-70% VO2peak) but not high intensity exercise (80% V02peak).

Pediatric Disorders

back to Populations

Standard Error of Measurement (SEM)

Adolescent Girls: (Pfeiffer et al., 2002; n = 57)

  • SEM = 1.24

Cut-Off Scores

Pediatric: (Hommerding et al., 2010; n = 41, mean age = 11.1)

  • Reported RPE on 15-point scale of 9 indicates light work

  • Reported RPE on on 11-point scale of 1 indicates very light work

  • Reported RPE on 15-point scale of 17 indicates hard work

  • Reported RPE on on 11 - point scale of 7 indicates very hard work

Criterion Validity (Predictive/Concurrent)

Concurrent validity

Adolescent Girls: (Pfeiffer et al., 2002; n = 57)

  • Excellent correlation (r = 0.60) with a power of 0.80

Adolescent Boys (Eston & Williams, 1986; n = 30; mean age = 16 (1))

  • Excellent: Correlation between RPE and power output: r = 0.78, p < 0.01

  • Excellent: Correlation between RPE and heart rate: r = 0.74, p < 0.01

Construct Validity

Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:Calibri; mso-fareast-language:EN-US;}

Convergent validity

Adolescent Girls (Pfeiffer et al., 2002)

●&苍产蝉辫;&苍产蝉辫;&苍产蝉辫;&苍产蝉辫;&苍产蝉辫; Excellent validity (%HRmax;r??) = 0.66, p < 0.05

●&苍产蝉辫;&苍产蝉辫;&苍产蝉辫;&苍产蝉辫;&苍产蝉辫; Excellent validity (%V0?max;r??) = 0.70, p < 0.05

Back Pain

back to Populations

Normative Data

Lumbar Disc Herniation (Dedering et al., 2010)

Patients’ characteristics, median and range, n = 15

 

All, n = 15

Men, n = 8

Women, n = 7

Age (years)

46 (27–65)

42 (27–65)

45.5 (37–55)

Height (m)

1.69 (1.60–1.92)

1.80 (1.65–1.92)*

1.66 (1.60–1.72)*

Weight (kg)

77 (55–102)

87.5 (63–102)*

72.5 (55–88)*

BMI (kg/m^2)

25.8 (20.7–33.1)

26 (22.7–31.6)

25.8 (20.7–33.1)

Pain duration (months)

8 (3–108)

7.5 (3–108)

9 (3–72)

Physical activity Roland-Morris (max score 20)

3 (1–6)

3 (1–4)

3 (2–6)

Oswestry (max score 60)

10 (3–20)

11 (6–16)

9 (3–20)

Self-efficacy (max score 64)

22 (14–38)

20.5 (18–38)

26 (14–37)

SF-36

44 (17–51)

46 (17–51)

34 (21–48)

–Physical Functioning

65 (25–75)

65 (60–75)

60 (25–75)

–Role Physical

20 (0–100)

20 (0–100)

10 (0–50)

–Bodily Pain

41 (22–74)

37 (22–64)

41 (41–74)

–General Health

65 (25–87)

59 (35–87)

67 (25–77)

–痴颈迟补濒颈迟测

40 (5–85)

33 (5–85)

50 (30–70)

–Social Functioning

63 (38–100)

69 (50–100)

63 (38–100)

–Role Emotional

66 (0–100)

66 (0–100)

100 (0–100)

–Mental Health

72 (40–92)

74 (48–92)

64 (40–80)

Interrater/Intrarater Reliability

Lumbar Disc Herniation: (Dedering et al., 2010)

  • Good interrater reliability (ICC = 0.85)

Construct Validity

Chronic low back pain: (Armstrong et al., 2005)

  • Moderate correlation for Peak SaO (Pearson's r = 0.66, p < 0.05)

  • Moderate correlation for peak Borg Rating of Perceived Exertion (Pearson's r = 0.75. p < 0.05)

Neuromuscular Conditions

back to Populations

Content Validity

Spina Bifida: (Crytzer et al., 2015)

  • Significant variance (τ = .70)

Parkinson's Disease

back to Populations

Criterion Validity (Predictive/Concurrent)

Predictive validity

笔补谤办颈苍蝉辞苍’蝉 (Penko, Barkley, Koop, & Alberts, 2017; n = 38; female mean age = 56.9 (5.5); male mean age = 58.7 (9.5); Hoehn and Yahr stage II-III: mild-moderate PD)

  • Excellent: Association between RPE and heart rate was r = 0.61, p < 0.001

  • Excellent: Association between RPE and work rate was r = 0.77, p < 0.001

Older Adults and Geriatric Care

back to Populations

Test/Retest Reliability

Frail Older Adults (Mendelsohn et al., 2008; n = 18; mean age = 82 (5) years; women, n = 3; men, n = 15)

  • HR & metabolic equivalents of task (METs) (ICC = 0.85-0.91)

Criterion Validity (Predictive/Concurrent)

Concurrent validity:

Older Japanese Adults: (Shigematsu, Ueno, Nakagaichi, Nho, & Tanaka, 2004; older group, n = 29; middle-aged group, n = 24; older group mean age = 75.5 (3.8); middle-aged group mean age = 46.9 (7.0); Toride City, Ibaraki prefecture, Japan participants)

  • Excellent: Mean correlation between VO2 and RPE in older age group (r = .95, p < 0.05)

  • Excellent: Mean correlation between VO2 and RPE in middle-aged group (r = .96, p < 0.05)

Bibliography

 

Armstrong, M., McDonough, S., & Baxter, D. (2005). Reliability and repeatability of shuttle walk test in patients with chronic low back pain...including commentary by Eiser N, Lemmink KAP, and Walsh DA. International Journal Of Therapy & Rehabilitation, 12(10), 438-443.

Borg, G. (1998). Borg’s perceived exertion and pain scales. Champaign, IL: Human Kinetics.

Borg G. Psychophysical bases of perceived exertion. Med Sci Sports Exerc. 1982;14(5):377-381.

Buckley, J.P., Eston, R.G., Sim, J. (2000). "Ratings of perceived exertion in braille: validity and reliability in production mode." British Journal of Sports Medicine 34:297-302.

Cabral, L. L., Lopes, P. B., Wolf, R., Stefanello, J. M. F., & Pereira, G. (2017). A systematic review of cross-cultural adaptation and validation of Borg’s rating of perceived exertion scale. Journal of Physical Education, 28(2853), 2448-2455.

Chen, M., Fan, X., Moe, S. Criterion-related validity of the Borg rateings of perceived exertion scale in healthy individuals: a meta-analysis. J Sports Sci. 2002;20:873-899.

Cleland, B. T., Ingraham, B. A., Pitluck, M. C., Woo, D., & Ng, A. V. (2016). Reliability and Validity of Ratings of Perceived Exertion in Persons With Multiple Sclerosis. Archives Of Physical Medicine & Rehabilitation, 97(6), 974-982. doi:10.1016/j.apmr.2016.01.013

Crytzer, T. M., Dicianno, B. E., Robertson, R. J., & Yu-Ting, C. (2015). Validity Of A Wheelchair Perceived Exertion Scale (Wheel Scale) For Arm Ergometry Exercise In People With Spina Bifida. Perceptual & Motor Skills, 120(1), 304-322. doi:10.2466/15.08.PMS.120v12x8

Dedering, &., Gnospelius, &., & Elfving, B. (2010). Reliability of measurements of endurance time, electromyographic fatigue and recovery, and associations to activity limitations, in patients with lumbar disc herniation. Physiotherapy 嫩B研究院 International, 15(4), 189-198. doi:10.1002/pri.457

Doherty, M., Smith, P.M., Hughes, M.G., Collins, D. (2001). "Rating of perceived exertion during high-intensity treadmill running." Medicine and Science in Sports and Exercise 33:1953-8.

Eng, J.J., Chu, K.S., Dawson, A.S., Kim, C.M., Hepburn, K.E. "Functional walk tests in individuals with stroke: Relation to perceived exertion and myocardial exertion." Stroke. 2002;33:756-761.

Eston, R.G., Faulkner, J.A., Mason, E.A., Parfitt, G. (2006). "The validity of predicting maximal oxygen uptake from perceptually regulated graded exercise tests of different durations." European Journal of Applied Physiology 97:535-41.

Eston, R.G. & Thompson, M. (1997). "Use of ratings of perceived exertion for predicting maximal work rate and prescribing exercise intensity in patients taking atenolol." British Journal of Sports Medicine 31:114-119.

Eston, R. G., & Williams, J. G. (1986). Exercise intensity and perceived exertion in adolescent boys. British Journal of Sports Medicine. 20, 27-30.

Eston, R. G., & Williams, J. G. (1988). Reliability of ratings of perceived effort regulation of exercise intensity. British Journal of Sports Medicine. 22(4),153-155.

Gillach, M. C., Sallis, J. F., Buono, M. J., Patterson, P., Nader, P. R. (1989). The relationship between perceived exertion and heart rate in children and adults. Pediatric Exercise Science. 1, 360-368.

Groslambert, A. & Mahon, A.D. (2006). "Perceived exertion : influence of age and cognitive development." Sports Medicine 36:911-28. Find it on PubMed

Hampton, S., Armstrong, G., Ayyar, M. S., & Li, S. (2014). Quantification of Perceived Exertion During Isometric Force Production With the Borg Scale in Healthy Individuals and Patients With Chronic Stroke. Topics In Stroke Rehabilitation, 21(1), 33-39. doi:10.1310/tsr2101-33

Hommerding, P., Donadio, M., Paim, T., & Marostica, P. (2010). The Borg scale is accurate in children and adolescents older than 9 years with cystic fibrosis. Respiratory Care, 55(6), 729-733.

Joo, K. C., Brubaker, P. H., MacDougall, A., Saikin, A. M., Ross, J. H., & Whaley, M. H. (2004). Exercise prescription using resting heart rate plus 20 or perceived exertion in cardiac rehabilitation. Journal of Cardiopulmonary Rehabilitation, 24(3), 178-184.

Karavatas S. G., & Tavakol K. (2005). Concurrent validity of Borg’s rating of perceived exertion In African-American young adults, employing heart rate as the standard. The Internet Journal of Allied Health Sciences and Practice. 3(1).

Knapen, J., van de Vliet, P., van Coppenolle, H., Peuskens, J., & Pieters, G. (2003). Evaluation of cardio-respiratory fitness and perceived exertion for patients with depressive and anxiety disorders: a study on reliability. Disability & Rehabilitation, 25(23), 1312-1315.

Lamb K, Eston R, Corns D. Reliability of ratings of perceived exertion during progressive treadmill exercise. Br J Sports Med. 1999;33(5):336-339.

Lamb, K. L., Eston, R.G. & Corns, D. (2006). "Reliability of ratings of perceived exertion during progressive treadmill exercise." British Journal of Sports Medicine 33:336-339.

Marriott, H. E. & Lamb, K. L. (1996). The use of ratings of perceived exertion for regulating exercise levels in rowing ergometry. European Journal of Applied Physiology. 72(3), 267-271.

Mendelsohn, M.E., Connelly, D.M., Overend, T.J., & Petrella, R.J. (2008). "Validity of values for metabolic equivalents of task during submaximal all-extremity exercise and reliability of exercise responses in frail older adults." Physical Therapy 88:747-56.

O'Neill M. E., Cooper K. A., Mills C. M., Boyce, E. S., & Hunyor, S. N. (1992). Accuracy of Borg's ratings of perceived exertion in the prediction of heart rates during pregnancy. British Journal of Sports Medicine. 26(2), 121-124.

Onodera K., & Miyashita M. (1976). A study of Japanese scale for rating of perceived exertion in endurance exercise. Japanese Journal of Physical Education. 21, 191-203.

Penko, A. L., Barkley, J. E., Koop, M. M., & Alberts, J. L. (2017). Borg scale is valid for ratings of perceived exertion for individuals with 笔补谤办颈苍蝉辞苍’蝉 disease. International Journal of Exercise Medicine, 10(1), 76-86.

Pfeiffer, K.A., Pivarnik, J.M., Womack, C.J., Reeves, M.J., & Malina, R.M. (2002). "Ratings of perceived exertion in braille: validity and reliability in production mode." Medicine and Science in Sports and Exercise 34:2057-61.

Pollock, B. S., Barkley, J. E., Potenzini, N., Desalvo, R. M., Buser, S. L., Otterstetter, R., & Juvancic-Heltzel, J. A. (2013). Validity of Borg ratings of perceived exertion during active video game play. International Journal of Exercise Science. 6(2), 164-170.

Psycharaksi, S. G. (2011). A longitudinal analysis on the validity and reliability of ratings of perceived exertion for elite swimmers. Journal of Strength and Conditioning 嫩B研究院. 25(2), 420-426.

Sage et al., 2013. "Validity of Rating of Perceived Exertion Ranges in Individuals in the Subacute Stage of Stroke Recovery." Top Stroke Rehabil 20(6): 519-527.

Scherr, J., Wolfarth, B., Christle, J.W., Pressler, A., Wagenpfeil, S., & Halle, M. (2012). Associations between Borg’s rating of perceived notion and physiological measures of exercise intensity. European Journal of Applied Physiology, 113, 147-155.

Shigematsu R., Ueno, L. M., Nakagaichi, M., Nho, H., & Tanaka, K. (2004). Rate of perceived exertion as a tool to monitor cycling exercise intensity in older adults. Journal of Aging and Physical Activity, 11, 3-9.

Tseng, B.Y., Gajewski, B.J., & Kluding, P. "Reliability, responsiveness, and validity of the Visual Analog Fatigue Scale to measure exertion fatigue in people with chronic stroke: A preliminary study." Stroke Res Treat. 2010;2010:7 pages.