While any exercise is better than no exercise, if you want to see results you need to exercise with high intensity.
There is a place for low to moderate-intensity exercise in training programs. But if you want to improve your performance, increase your cardiovascular strength and make progress, then you need to put in the effort.
You can use the Rate of Perceived Exertion Scale—RPE Scale—to assess if you’re working hard enough or if you have the capacity to go harder.
Using the RPE Scale can help you to take your training to the next level. It can also help you to avoid overtraining, by listening to your body.
What is RPE?
RPE stands for Rate of Perceived Exertion. This means how hard you feel that you are working when you’re exercising.
The RPE Scale is based on physical sensations. Therefore, the only person who can measure your RPE is you! Nobody else can feel the physical sensations you’re feeling during and after exercise, so nobody can measure your RPE for you.
You assess your RPE using metrics like your heart rate, respiration rate, how fatigued your muscles are, and how much you’re sweating.
Why Should I Use RPE?
Understanding how to measure and use your RPE data can help you adjust your workout up or down in intensity to help you reach your goals faster.
Knowing your RPE can help you to maximize your workout by pushing yourself harder on days when your body is feeling stronger. But it also helps you to maximize your recovery by understanding how your body works and when it is primed for exercise and when it’s not.
If you aren’t feeling 100 percent on a day, you can adjust your training intensity so that you don’t end up feeling worse after your training session.
But if you slept well and you have extra energy, using your RPE will allow you to make the most of the day.
There are Two Types of RPE Scales
The original way of measuring your RPE is called the Borg Rating of Perceived Exertion. It ranges from 6 to 20, where 6 is the lowest level of exertion and 20 is an all-out effort.
A level of between 12 and 14 on the Borg RPE Scale is considered to be moderate. Around 9 is considered to be very light, and 19 would be extremely hard. You assess these things based on your heart rate, breathlessness, and muscle fatigue.
The Borg RPE Scale is closely linked to heart rate. You can get a good estimate of your exertion level by dividing your heart rate by 10. For example, if your heart rate is 100, your exertion rate should be at 10. If it’s at 160, your exertion rate should be around 16. That’s why this scale starts at 6—60 beats per minute is an average healthy heart rate at low exertion.
This is just an estimate, though. It can vary depending on a person’s fitness level. But if you have a heart rate monitor or a smartwatch with a heart rate function, it can help you to get an idea of what you should be aiming for in terms of exertion.
The second scale—modified RPE Scale—only ranges from 0 to 10, with 0 being the least exertion and 10 being maximum exertion. Moderate exertion falls at about 4 on the modified RPE Scale.
Instead of being based on heart rate, the modified RPE Scale is more closely linked to breathing.
So while doing light activity, you should be able to continue a full conversation without struggling for breath. If you can’t say more than a few words or breathe in deeply, then it counts as heavy exertion.
Where to Start
It is a good idea to learn both scales if you can remember them. It’s easy to correspond the numbers to the intensity of your workout, no matter how new or advanced you are.
All you need to remember is the range of numbers and that the higher the number is, the more the exertion.
You can use the RPE Scale at any point during your workout. Just assess your breathing, heart rate, and muscle fatigue and choose a number.
The Modified RPE Scale Monitoring 0-10
The modified RPE Scale is the more straightforward of the two for many people. If you don’t have a heart rate monitor or don’t want to check it in the middle of your workout, the modified scale may be easier to assess, as you can simply monitor your breathing.
Zero is the amount of exertion when you’re just standing. 2 is considered to be light, and 3 to 4 is moderate exercise. 5 and 6 count as heavy exercise, and 8 to 9 are very heavy. 10 is maximum exertion, the hardest you’ve ever exercised in your life.
At 0, you can sing comfortably or breathe without even thinking about it. At 10, you won’t be able to say more than two or three words before gasping.
The Original Borg Scale Monitoring 6-20
The original Borg RPE Scale is helpful if you want to monitor your heart rate at the same time. If you have a smartwatch or a heart rate monitor then it’s easy to assess your performance based on your heart rate.
Your fitness level will affect your heart rate. Beginners will have a higher heart rate, while experienced runners will have a lower and more stable heart rate. You should calculate your maximum heart rate by subtracting your age from 220.
Once you know your maximum heart rate, you can also calculate how intensely you’re working out by your heart rate. Moderate intensity is between 60 and 75 percent of your maximum. High-intensity is between 75 and 90 percent.
On the Borg REP Scale, 6 is no exertion at all and correlates to meditating in a seated position. Gentles stretching or yoga—extremely light exertion. Everyday relaxed walking would be a 9 on the scale. 13 is “somewhat hard”, which could be a jog or light weightlifting. Running at a speed falls at around 15, which is hard exertion. HIIT training would be at about 19, and maximum exertion would be 20.
You Can Take Your Heart Rate Manually by Following These Steps
Using your first two fingers—not your thumb—feel the inside of your wrist until you find the beat. You can count the number of beats in 60 seconds for the most accurate measurement, but you can also count in 15 or 30-second blocks.
If you count your pulse for 15 seconds, multiply it by 4 to get your beats per minute. If you count for 30 seconds, multiply it by 2.
How to Use the Borg Scale
It may take some time to get used to considering how you’re feeling during an activity. In order to get usable data, you will need to periodically assess your own physical feelings while you’re exercising.
At first, try not to focus on one specific thing, like heart rate or breathing. Just consider how you feel and how much you think you’re exerting yourself. If you’re feeling very fatigued, you may choose 17 or 18 on the Borg RPE Scale.
To estimate your heart rate at that time, multiply the number you chose by 10. If you are wearing a heart rate monitor, you can check it to see how accurate your assessment was.
When you are aiming for the target heart rate zone, your ideal exertion level on the Borg RPE Scale should be between 12 and 16. If you notice that your RPE for a specific activity has decreased, that’s an indication that your fitness level has improved!
Which one is better?
Many runners find the modified RPE Scale to be easier to work with. It’s a more logical scale—from 0 to 10—and many find it easier to quickly assess their breathing rather than trying to estimate heart rate or check their smartwatch in the middle of an exercise.
But they are both effective and it depends on your goals and what you’re more comfortable with. If you already check your heart rate periodically, then you may be comfortable with using the Borg Scale if you are okay with the range from 6 to 20.
Train at a Variety of Intensities to Maximize Your Results
Whichever scale you choose and whatever kind of training you’re doing, using the RPE can help you to adjust your intensity to maximize your results.
Training at the same intensity every time can lead to overtraining, especially if you don’t listen to your body. It’s wise to vary your training intensity, not only to prevent overtraining and injury but also because it can help you break through workout plateaus or ruts.
The more you use your RPE, the more you will get used to assessing yourself at any given time and adjusting your intensity. Over time, you will find that your workouts feel better and you recover better when you’re working out at the right intensity on any given day.