The terminology we use to describe output levels during training is quite useful. Today we’re going to discuss 2 popular methods of estimating effort. They are Rate of Perceived Exertion (RPE) and Repetitions in Reserve (RIR).
Potato versus Pototto. Or you might say Tumaytuh while another utters Tohmottoh. I think you get my drift. RPE and RIR are great assets in training and each has its strong points.
Like so many things in training in performance, I’m not inclined to say “always” use this approach and “never” do that one. It just depends on the specific context and athlete we are considering. As opposed to being wishy-washy or on the fence, I look at RPE and RIR as tools that I utilize when one of them fits best with the situation at hand. My choice might not be yours, but I’ll explain my rationale. Let’s examine each effort descriptor and then provide a few examples.
RPE was developed by Swedish scientist Gunnar Borg in the early 1960’s. The original studies looked at perceived effort during stationary cycling and utilized a scale which went from 6-20. Each number was intended to roughly correlate (when multiplied by 10) with the heart rate an exerciser would exhibit at a given effort level. There were also terms such as “very, very light (7)” and “very, very hard (19)” associated with each number.
The Borg scale was later simplified to the Modified Borg Dyspnea Scale and featured a rating of 0-10. The dyspnea, or labored breathing, characterized the intensity of activity. Variations of this scale are popular today and in use in a variety of athletic and fitness activities.
Essentially, RPE asks the exerciser to answer this question: “What percentage of your absolute maximum effort are you applying right now?” For example, an RPE of 8 would roughly correlate with giving about 80% of total potential output. And so forth.
Because RPE depicts “how hard you are trying,” you can use it in almost any application. It’s like saying, in the moment, what effort are you giving? That stated, I like to use RPE most in steady-state or explosive output scenarios.
Steady-state training such as cycling, running, swimming, and rowing match up very well with RPE. Runners and swimmers may correlate pace and heart rate with RPE. Cyclists and rowers match up well with power meters. The beauty of RPE is its simplicity. Over time, the athlete (as long as he/she is well rested) knows almost exactly the RPE number – down to the tenth – that describes the speed, heart rate, or power they are delivering.
RPE also works very well with explosive activities such as Olympic lifts or plyometrics. It can describe the percentage of max weight in a lift or the level of intention/difficulty in a jump. RPE can also describe sprints, but I usually like to further clarify the rating as a percentage of max velocity.
RIR, on the other hand and in my studied opinion, really shines in resistance training. RIR tasks the exerciser with determining “How many reps do I have left in the tank when I conclude my set?” This becomes a beautiful metric because it automatically encourages self-exploration and ensures (particularly at RIR 3-2-1-0) the exerciser will give a realistic, high-quality, effort.
Explaining that last statement further, let’s say you are repping on the bench press. You are going for an RIR of 1 because the literature clearly states that you will maximize the stimulus for strength and hypertrophy adaptations if you approach momentary muscular failure. Instead of shooting for a predetermined number of reps, you keep going until you barely complete your last rep and feel like maybe, just maybe, you could have done only one more.
RIR allows you to practically ignore rep ranges. Now, yes, we do recognize that there are specific benefits to working hard with loads which mandate certain rep ranges. Heavy weights and low reps (because you can’t do many reps with such a heavy weight) drive strength. 6-15 reps in the “pump range” – as long as you approach at least partial failure – have always been considered a hypertrophy zone. But here’s the kicker. As long as you truly go to the point where you only have a couple reps left, you are still making progress. This means that, for Lifetime Athletes (who often have the accumulation of wear and tear in their beastly bodies), even light loads can be very beneficial in resistance training, and it’s arguably safer. Research supports this and the recent interest in blood flow restriction training goes down that road even further.
Now we get to the personality thing that I’m always talking about. That’s the primary reason why one person chooses the RPE potato over the RIR pototto. Whatever floats your boat. Whatever blows your hair back. As long as you like what you’re doing, and you find it meaningful and effective, all good.
If we focus specifically on resistance training, a trend will reveal itself.
Trainees who are drawn to structure, organization, trackers, wearables, spreadsheets, and schedules will generally prefer RPE. And they’ll be inclined to match it up with percentage of repetition maximum (%RM), total workload, and the like.
“Go by feel” types tend to love RIR because they don’t have to deal with all the minute details (which they don’t love) and can just hammer in the moment when the set nears its end.
We can even loosely correlate RPE and RIR, although they may not always be identical. But if you are doing resistance training in a set of 10, it’s a pretty good relationship. In that instance, an RPE of 8 would be an RIR of 2, or an RPE of 9 matches an RIR of 1.
You don’t always have to use these descriptors. Some types of training, such as mobility work, don’t require this element. And, there are also days where you neither want nor need to monitor very much. But using either RPE or RIR to gauge where you’re at on the day in accordance with your program goals and schedule, is one of the hallmarks of intelligent training that leads to lifetime success in health, fitness, and performance.
Thanks for joining me today.