The intensity with which we exercise is one of the most important aspects of training and physical fitness. Not only can we utilize exercise intensity to determine if we’re working hard enough, we can use it just the same to determine if we’re not.
There are many ways we can measure this rate of intensity. Common methods include using the talking test, analyzing target heart rate zones, and following the Borg rating of perceived exertion scale, or RPE for short.
The talking test simply involves talking while exercising: The greater the intensity of the physical activity being performed, the harder it should be to talk. Target heart rate zones, on the other hand, incorporate how quickly your heart beats in relation to your level of physical intensity, and measuring them requires the use of a heart rate monitor. But what is RPE?
The rate of perceived exertion is often the simplest method one can use to determine how strenuous a bout of physical activity is. And as a result, it’s a method worthy of understanding before your next workout begins.
What Is the Rate of Perceived Exertion?
You may find yourself a bit confused by the Borg scale of perceived exertion. After all, who’s Borg anyway?
Borg refers to Gunnar Borg, a Swedish professor who introduced the world to the field of exertion in the 1960s. As a result of his work, he went on to receive international acclaim for developing methods that accurately measure the intensity of an exercise experience. Both the Borg Scale and Borg cr10 Scale, a separate scale used to measure perceived breathlessness, have since been utilized around the world as a means to quantitatively track the feeling of exertion.
Perceived exertion is simply how hard you think your body is working. We can utilize the many components of exercise that change with our intensity in an attempt to understand just how hard that intensity may be. For instance, our breathing becomes faster to supply more oxygen to the heart as sweat begins to build and muscles grow more fatigued by the minute. These factors, and others, provide us with insight into the intensity of our physical activity.
While analyzing these traits may not be as accurate as measuring target heart rate zones, they can still provide us with a quantitative number when we utilize the rate of perceived exertion scale.
The Rate of Perceived Exertion Scale
To determine our rate of perceived exertion, first we must understand the Borg rating of perceived exertion scale. When utilizing this scale, it pays to be working out in some form of moderate-intensity or vigorous-intensity exercise. Only then can we focus on the many bodily facets that come with exercise, paying mind to how we feel in the moment.
The scale is simple in nature and consists of 15 different ratings, each one indicative of how hard your exercise intensity may be. Beginning at six (a number chosen to match heart rate measurements), where no exertion is occurring at all, the scale climbs higher and higher before topping out at 20, or what we refer to as maximum effort intensity. Different zones of the scale are often representative of the activity being performed.
For instance, as previously noted, an activity intensity rating of 6 is the equivalent of no exertion at all. But as the scale climbs higher, so too does the intensity grow. A rating of nine is considered very light intensity, often consistent with the act of walking casually down the street. A rating of 13 may be equivalent to sustained effort that’s difficult yet attainable. And at 15 things grow harder still, until slowly the scale creeps to 20 — the point at which maximum energy is being utilized and likely can’t be sustained for long. Anaerobic energy consumption takes place at this point, until soon the body must quit.
But what about those numbers in between? Here’s a more detailed explanation of each level of exertion on the Borg RPE scale.
- 6: No exertion with very little movement
- 7: Extremely light and simple movements while in place
- 8: Casual physical movements
- 9: Very light intensity, such as walking down the street
- 10: Effort begins to increase marginally, but remains painless
- 11: Running at this intensity is easy, and you can talk consistently
- 12: Light intensity that builds aerobic endurance
- 13: Moderate activity, you can feel the intensity build but can push on as well
- 14: Breathing grows deeper
- 15: Talking becomes difficult and comprises one or two-word answers as shortness of breath occurs
- 16: The point at which steady state occurs. This is “activity that achieves a balance between the energy required by working muscles and the rate of oxygen and delivery for aerobic production.”
- 17: The anaerobic threshold is reached, and intensity becomes very hard
- 18: Breathing becomes vigorous and talking is impossible
- 19: Extremely difficult intensity, you’re hoping the pain will end soon
- 20: Maximal exertion or maximum effort
How to Use the Borg Scale of Perceived Exertion
Utilizing the Borg Scale of Perceived Exertion is a rather simple task. Simply warm up for exercise as you normally would, and then begin your workout. After a few minutes of the routine, take stock of how your body feels. Notice how hard you’re breathing, how much you’ve been sweating, and how your muscles feel in action.
From there, simply use the knowledge you’ve gained to give yourself a score that feels both accurate and true to you. If the score feels either too high or too low, increase or decrease the intensity of the task accordingly.
While a sprinter or rower may find themselves sustaining scores of 19 or above for extended periods of time, chances are you won’t be the same. Because your fitness level is directly related to your exertion level, how physically fit you are will determine your score.
The Borg Scale and Your Heart Rate
Unbeknownst to many, this rating scale can actually provide an accurate estimate of your heart rate while in the midst of activity. To determine your approximate heart rate, simply multiply your Borg’s rating (RPE) by 10.
For instance, an RPE score of 16 × 10 = 160 beats per minute.
The scale was designed with the average healthy adult in mind. Because both age and physical condition affect maximum heart rate, heart rate zones for different levels of intensity will change as a result.
Why the Borg Scale of Perceived Exertion Matters
The Borg Scale is just one of the many methods you can utilize to determine exercise intensity. Yet of the many that exist, it’s often considered one of the easiest to use on a consistent basis, as no form of equipment or controlled environment is needed.
To gauge your fitness levels and the intensity of your exercises, use this method when possible, and if you can, consider using multiple methods to ensure your results are accurate and reflect what you need to know to improve your health.