At one point in our lives we have all heard the expression, “how hard does this feel?” Even at the doctor’s office, we are asked to rate our level of pain on a scale of 0-10. Rate of perceived exertion (RPE), has been a term used since the very beginnings of endurance exercise. Way before we had heart rate monitors, SPO2 trackers, heart rate variability, and power meters; we simply had our own thoughts on how an effort feels. Turns out: this “simple” measure is more often than not, still critical to training.
Defining RPE
Let’s begin by first outlining the scale of RPE. RPE is based on a 0-10 scale, where 0 is no effort, 10 is you going to maximal exertion, and then everything in between.
Rating 1-3: warm-up/cool down
This is the lowest intensity we can maintain for periods of time. These types of efforts borderline on boredom. This is you going for a walk or an easy ride, and your breathing is a good indicator of this effort.
Rating 4-5: endurance/zone 2/base
These efforts may have you notice an increase in your breathing rate. While there is an increase, you are still able to talk in full sentences without taking a breath. Many people do not truly perform their “endurance” efforts in this zone. What some consider talking in full sentences, is really them starting a sentence, pausing for a moment to breathe, then finishing the sentence. This zone is performed without taking a pause.
Rating 6: Tempo
We see an increase in our breathing rate and now we are breathing heavily. We can still talk, but it is not full sentences, but phrases. This type of effort is skill controlled and we can count our breaths at a regular interval now.
Rating 7-8: Threshold
This type of effort coincides with our FTP (functional threshold power) as well as our running threshold pace. We now have another shift in breathing that follows a linear fashion at first, and then increases exponentially. This effort requires our full concentration and is difficult to keep up.
Rating 9-10: VO2 +
These types of efforts are very uncomfortable and our breathing is difficult, to say the least. These efforts involve a lot of internal dialogue, and most of it….not pleasant!
When using an RPE scale like this, we have different types and times for when to use it. For example, we can have an “In-Workout RPE” where this is instantaneous feedback on how we feel in our head/heart/lungs/ and limbs all put together for one value. The great part is that there is no wrong answer for how you feel. As many say, “it is, what it is.”
You can also use RPE as a target for a workout. Instead of a session where it reads, “threshold power for 5 minutes,” it would read: “5 minutes at an RPE of 7.” So if you’re currently at an RPE of 1 then you need to increase the effort. If you already feel like you’re at an RPE of 10, then it is time to pump the brakes and dial it back to get to your “7.”
So why do we still say that RPE is just as valuable of a metric as heart rate, power, etc? It is subjective and not measurable, there must be a mistake, right? Let’s take heart rate for example: if you were solely basing training on this metric; when you get into periods of heavy training, your max heart rate can drop and therefore become manipulated. Though your heart rate has dropped, the perception of an effort does not change. Perhaps your power numbers are low, but your RPE is still high, don’t fear. Depending upon your training status and where you are in a training block, this can be either good or bad. Never disregard or shrug off how you feel, more often than not this “feeling” is right on the money!
PSR – Post Session Rating
Your post-session rating (PSR) may be a new term to many of us, but it is backed by research. This rating is not what you feel during a workout, it is not how you think you are going to feel, it is how you felt about the workout 20-30 minutes post-session. This rating helps to give you a real evaluation of the workout as a whole.
Simple question: how was your workout? If most of us answered this immediately following 10×2 minutes at MAP (maximal aerobic power), we’d probably answer, “terrible!” in between gasps for air. Now, if you were to be asked this question 30 minutes after you finished, your answer may carry a different tune, “it was hard, but definitely felt strong during the efforts.” PSR is being able to separate ourselves from the workout.
With PSR there is also a reward component. We may perceive our discomfort entirely differently whether we won or lost in a race, or hit our target power during a workout. There are 1000s of articles that utilize this PSR value based on accumulated fatigue. As it turns out: PSR is the most accurate in being able to establish what our training load was, and what you may need to do to modify this load. In fact, PSR feedback is more accurate than other physiological and mechanical feedback.
Heading out for a ride and realizing you forgot your heart rate monitor? No stress. Instead, focus on how you are feeling during the ride, and then take a moment to assess how it felt 20-30 minutes after. These factors are just as important as any metric you may objectively measure. RPE and PSR are clearly dependent upon the athlete’s experience, athlete tolerance, and training focus. The best part about these metrics is that there is no wrong answer. The hardest part is being honest with yourself. Is this effort really a five or is it actually more straining than you are letting on? There is a fine line between cooked and overcooked. It is better to arrive on race day a little underdone, than over.