What if my Legs can’t go Another Minute
If you are new to an exercise program, don’t worry about rating your exertion. You will need to condition your body to the exercise before RPE will be accurate. RPE is designed to reflect the cardiovascular and metabolic impact of exercise intensity — how hard your heart is working and how many calories you are burning. So when local fatigue dominates the scene, RPE will not be a reliable indicator of true exercise intensity. But this doesn’t mean you should ignore fatigue. Pain always calls for analysis and response: strengthening, stretching or resting overloaded muscles and joints should help.
Why should I bother with perceived exertion?
Even if you are in a program that uses heart rate monitors to keep you below a specified heart rate, monitoring RPE can be beneficial for you. Over time, you may find that it becomes fairly easy to replicate your target exercise intensity just by sensing how difficult an exercise feels.
This ability to sense exercise intensity can be helpful in your everyday life. You will feel confident that when you are performing tasks of daily living such as walking to the store or going up stairs, you are not going above your target zone.
Why does the scale run from 6 to 20?
The research done by the scale’s originator, Swedish exercise physiologist Gunnar Borg, correlated RPE with exercise heart rate in young male subjects. So 6 represented a resting HR of 60, and 20 a maximal HR of 200 beats per minute. This relationship may or may not hold true for you, but it does not detract from the scale’s usefulness as a tool to measure exercise intensity.