Last updated: 3 October 2026
Reviewed by Jordan Morley, FA Level 2 Football Coach
The Borg RPE scale runs from 6 (rest) to 20 (maximal effort), designed so that the number multiplied by 10 approximately corresponds to heart rate. A rating of 12-13 (‘somewhat hard’) corresponds to approximately 120-130 bpm. The scale preceded modern zone systems and is still widely used in clinical and research settings. A 6-20 scale is Borg’s original; his modified CR10 scale (0-10) is more widely used in practical fitness settings as the simpler alternative. Both versions are well-validated against physiological markers of exercise intensity.
- Scale: 6 (rest) to 20 (maximal)
- Rating × 10 ≈ heart rate
- 12-13 = moderate; 17-18 = very hard
- Modified CR10 (0-10) is more commonly used today
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The Borg RPE scale (originally 6-20, with a popular simplified 1-10 version also widely used) lets coaches prescribe and monitor training intensity without needing a heart rate monitor or lab equipment — because perceived effort correlates reasonably well with physiological markers like heart rate and lactate, a simple 'how hard did that feel' rating remains a genuinely useful, low-cost training tool even in highly equipped programmes.
FAQ
How does the Borg scale work?
The original scale runs from 6 to 20, roughly correlating to heart rate when multiplied by 10 (so a rating of 13 corresponds to roughly 130bpm for many people); a simplified 1-10 version is also commonly used in practice.
Is RPE a reliable way to measure training intensity?
Yes, reasonably — RPE correlates well with objective markers like heart rate and blood lactate in trained individuals, making it a practical, equipment-free way to gauge and communicate training intensity.