How to Use Perceived Exertion in Racing and Training
As athletes in 2022, we have a wonderful array of tools as our disposal to monitor and quantify our output, our recovery, our adaptations to training, and more. One of the best tools we have, though, is our own body.
Here's an overview of where the notion of RPE came from, and how you can use it in your racing and training.
Swedish science: Rating of Perceived Exertion (RPE)
Rating of perceived exertion (RPE) is a term we use in coaching to measure how hard you’re working during exercise.
I bet you have been asked at some point in your life, “On a scale of 1-10, how hard are you working?” This is RPE.
The 1-10 scale is the most common, with 1 being “not at all” and 10 being “maximal effort.”
If you go to the doctor’s office or to the physiology lab to have testing done, they may ask you the same question, but on a scale of 6-20. Why 6 to 20, you ask? Here's why.
During the 1960s and ’70s, a pair of Swedish scientists, Dr. Gunnar Borg (a psychologist) and Hans Dahlström (a physiologist), designed the first studies to investigate perceptions of physical effort and sensations of pealing resistance on a cycle ergometer. They wanted to know more about how people felt in relation to their physical response to exercise.
As a result of these studies, Dr. Borg developed the Rating of Perceived Exertion and the Category Ratio-10 scales. The Borg scale is based on the numerical anchors of 6-20, with 6 being no effort and 20 being maximal, because they were intended to correspond loosely to heart rate when multiplied by 10.
Dr. Borg warned not to take this correlation too literally because "the meaning of a certain heart rate value as an indicator of strain depends upon age, type of exercise, environment, anxiety, medication and other factors."
In 1986, the ACSM began recommending the Borg scale to be used as a guide to regulate and monitor exercise intensity in their Guidelines for Exercise Testing and Prescription, and because of this, has become a world-wide accepted guideline for responsible exercise practice for the past four decades.
The Borg Category Ratio scale was modified from the Borg 6-20 scale in order to take physical pain into account as well as physical tiredness, and uses a 1-10 scale, rather than 6-20.
While Coach Suzie had a power meter on her bike, she raced largely on RPE at the 2022 Xterra National Championships, where she won her fifth U.S. national title in July.
Training with RPE
RPE is the simplest way to gauge your effort or intensity of exercise. You don’t need any tools, devices or gadgets. It costs nothing. All it takes is a little thought and attention to how your body feels at that moment in time. You can use it as the sole metric to guide you through your training efforts, or in combination with tools like a heart rate monitor or a power meter.
Many coaches recommend that athletes always use RPE when training as a backup form of measurement. What if your power meter goes out in the middle of a race or key workout? You need to know how to pace and judge your effort without a power meter, otherwise you’re likely to find yourself overcooked in no time.
The CR 1-10 scale is a little easier for most people, so we’ll save the Borg 6-20 scale for the lab and use the 1-10 scale in training plans. Let’s break it down and see how it matches up with heart-rate and power training zones.
RPE 1-2: Zone 1/Less than 55% power
Very light effort, you should be able to maintain this effort for a very long time. Mostly used for warm up, cool down and active recovery.
RPE 3-5: Zone 2/Endurance/56-75% power
Light to moderate effort. Breathing rate elevated but able to maintain a conversation in full sentences!
RPE 6: Zone 3/Tempo/76-90% power
Upper end of moderate effort. Further increase in heart and breathing rates, talking limited to speaking in phrases now.
RPE 6.5: Sweet Spot/84-97% power
Moderate to Hard exercise- This effort is hard, but not too uncomfortable and you could maintain it for an hour or more.
RPE 7: Zone 4/Threshold/98-104% power
Vigorous/hard exercise, Labored breathing, maintaining this effort requires concentration and most people prefer not to try speaking at this intensity.
RPE 8: Zone 5/VO2 Max/104-120% power
Very hard exercise. Heavy breathing, high heart rate, no talking. This is the hardest effort that you can maintain for no more than 5 minutes.
RPE 9: Zone 6/Anaerobic Capacity/full gas - 120%+
Maximum, all out effort. Cannot speak during and can only maintain effort for a short time, up to 1 minute.
RPE 10: Neuromuscular Power/130%+
All out, very short sprints lasting less than 30 seconds.
Using RPE in testing and racing
Most power tests and lactate threshold assessments have you ride for 20 minutes at your best sustainable effort to determine your training zones. Those zones are set so that you know how hard your training rides should be. Endurance rides are a different intensity than sweet spot intervals which are different from sprints.
When it comes to testing, you want to go as fast as you can for the 20 minutes, but you also don’t want to start too fast and blow up, which happens all too often. The best method is to try and use a negative split technique. This is hard because you’re probably feeling pretty rested and motivated, and don’t want to hold back because you fear it will slow you down. But just the opposite is true; if you start the 20-minute effort a little conservatively (shoot for an RPE of 6.5 or 7) and increase the effort a little after 10 minutes (increase to RPE 7.5), then again at 15 minutes (increase to RPE 8-8.5), you’re likely to go further and faster.
Using RPE when racing can be more helpful in certain races and situations than others. In a triathlon or a time trial, where it’s a fairly controlled situation- just you and the course, RPE is great. You can settle into the effort that you’ve dialed in and set as your target race pace while training. You can learn the RPE that matches your goal race pace so you know what that power output and overall effort feels like in every aspect.
Here are some things to pay attention to as you learn your zones in terms of RPE, heart rate, and power:
- What's your heart rate?
- How hard and deep are you breathing?
- How much muscular force is required of the legs?
- How hard are you pushing on the pedals in order to go that fast or slow?
- Think about the effort required and the sensations you feel when riding at threshold versus a recovery ride.
Now think about a road race where the pace is changing frequently because of attacks, climbs, and the rhythm of racing. You can’t exactly sit at your “target race pace” and get comfortable, so while it might be useful if you decide to go on the attack, or to pace yourself up a long climb, it’s going to be something that you use off and on throughout the race as you ride however you need to ride based on what’s happening around you.
Suzie Snyder is a multi-time Xterra National Champion, Xterra World Champion podium finisher, and a USA Triathlon certified coach with a Master's Degree in Exercise Science. She has enjoyed coaching everyone from triathletes of all levels to tactical athletes like the FBI's Hostage Rescue Team, the US Army 10th Special Forces Group and the Colorado Springs SWAT Team and K9 Units.