The Borg Scale: Rate of Perceived Exertion (RPE) & Dyspnea

In cardiopulmonary rehabilitation, objective markers like Heart Rate and SpO2 don't always tell the whole story—especially if a patient is on Beta-Blockers. The Borg Scale allows us to quantify the patient's subjective experience of effort. There are two versions: the Modified (0-10) scale for dyspnea and the Original (6-20) scale for heart rate correlation. Knowing which to use is critical for safe prescription.

1. Modified Borg Scale (0-10)

Best For: Dyspnea (Shortness of Breath) and General Fatigue.
Commonly used in COPD, Asthma, and Pulmonary Rehab.

Score	Description	Clinical Implication
0	Nothing at all	Resting state.
0.5	Very, very slight	Just noticeable.
1	Very slight
2	Slight
3	Moderate	Target Zone for COPD Rehab.
4	Somewhat Severe	Upper limit for safe exercise in most pulmonary patients.
5	Severe	Slow down or rest.
7	Very Severe
10	Maximal	Panic zone. Emergency.

2. Original Borg Scale (6-20)

Best For: Cardiac Rehab and Healthy Populations.
Why 6 to 20? It is designed to correlate with Heart Rate. If you multiply the Borg score by 10, it approximates the HR of a young adult (e.g., Borg 12 ≈ 120 bpm).

Score	Description	% Max Heart Rate
6	No exertion	Rest (60 bpm)
9	Very Light	Warm-up / Recovery
11	Light	Aerobic threshold
13	Somewhat Hard	Target Zone (12-14). Approx 60-70% Max HR.
15	Hard (Heavy)	Anaerobic threshold
17	Very Hard	Athletic performance zone
20	Maximal exertion	Max HR (200 bpm)

3. Clinical Correlation: The "Talk Test"

When you don't have a chart handy, use speech as a marker for intensity.

Activity Level	Borg (0-10)	Borg (6-20)	Talk Test Result
Light	0 - 2	6 - 11	Can sing a song while doing it.
Moderate (Goal)	3 - 4	12 - 14	Can talk in full sentences, but cannot sing.
Vigorous	5 - 7	15 - 17	Can only speak a few words at a time.
Maximal	> 7	> 18	Cannot talk at all.

4. How to Instruct the Patient

Standardized instructions ensure accuracy. Do not just ask "How are you?"

Script: "This is a scale that asks you to rate how hard you feel your body is working.
0 is sitting in a chair doing nothing.
10 is the hardest work you have ever done (like pushing a car uphill).
Based on your breathing and muscle fatigue, give me a number."

5. Revision Notes for Students

Modified (0-10): Non-linear. Used for Dyspnea/COPD. Target: 3-4.
Original (6-20): Linear. Used for Cardiac/HR. Target: 11-13 (12-14).
Math Trick: Borg 6-20 score x 10 = Approx Heart Rate.
Why use it? Essential for patients on Beta-Blockers (blunted HR response) or with Atrial Fibrillation (irregular HR).

6. FAQs

Q1. Why does the original scale start at 6?

Because Gunnar Borg designed it to match heart rate ranges from 60 bpm to 200 bpm. 6 corresponds to 60 bpm (Rest).

Q2. My patient says "2" but is gasping for air. What do I do?

Believe the clinical signs. Some patients minimize symptoms (stoicism) or misunderstand the scale. Re-educate them: "If you can't talk, that is not a 2. That is at least a 5 or 6." Use the Talk Test to calibrate them.

Q3. Can I use the 0-10 scale for pain?

Yes, the 0-10 format is universal (VAS - Visual Analog Scale) and is commonly used for pain, fatigue, and breathlessness. Just be clear about what you are asking them to rate.

7. 10 Practice MCQs

Q1. The Borg Scale of 6-20 is designed to correlate with:

Answer: B) Score x 10 = Estimated Heart Rate.

Q2. On the Modified Borg Scale (0-10), the target zone for COPD rehab is typically:

Answer: B) This level ("Moderate") induces training effects without causing distress.

Q3. A score of 13 on the Original Borg Scale corresponds to:

Answer: A) 13 is the classic aerobic training threshold.

Q4. Why is RPE preferred for patients on Beta-Blockers?

Answer: B) A patient might be working maximally but their HR only shows 90 bpm due to the meds.

Q5. If a patient can sing while exercising, their intensity is:

Answer: A) They have too much reserve breath; they need to work harder.

Q6. The description "Very, very slight" corresponds to which score on the 0-10 scale?

Answer: B) It represents barely noticeable effort.

Q7. RPE stands for:

Answer: C) Ideally described as "how hard you feel your body is working."

Q8. A Borg score of 19 (6-20 scale) suggests:

Answer: C) Correlates to ~190 bpm, near maximal effort.

Q9. Which scale is generally preferred for Dyspnea (Breathlessness)?

Answer: B) The 0-10 scale is more intuitive for quantifying symptoms like shortness of breath.

Q10. If a patient reports a Borg score of 5 (Severe) on the 0-10 scale during rehab, you should:

Answer: C) A score of 5 is generally the upper safety limit for clinical populations.

References

• Borg, G. A. (1982). Psychophysical bases of perceived exertion. Med Sci Sports Exerc.
• ACSM. (2021). ACSM's Guidelines for Exercise Testing and Prescription (11th ed.). Wolters Kluwer.
• AACVPR. (2020). Guidelines for Cardiac Rehabilitation. Human Kinetics.