The Ins and Outs of RPE: Part 2: Putting RPE to Use

Last week, in part 1, we looked at why we use RPE over percentages to assign and track intensity. This week we will go into the history and details of what RPE is. 

RPE stands for Rating of Perceived Exertion, and it is a subjective measure of how hard you are working. RPE is a numerical value between 0 and 10 with 0 being complete rest and 10 being maximal effort. RPE is something that is always there, no matter what. At the end of the set, you have given a certain amount of effort regardless if you track it or not, so we might as well track it because it can tell us a bunch of useful information (link last week's article). Many people complain that RPE is inaccurate, or they do not know how to judge RPE accurately, and we will be the first to admit that RPE is a skill that gets better with practice. 

Photo taken from: https://simplifaster.com/articles/use-rpe-team-sports/

Gunnar Borg introduced the world to RPE in the late 1950s/early 1960s. This scale original use was in the Cardiac Rehab world as a way to gauge the intensity of exercise done by cardiac patients. Since people undergoing cardiac rehab can perceive an activity as more effortful, then their heart rate suggests because of pulmonary responses, a method was needed to apply intensities to these patients appropriately. The Borg Scale was originally from 6-21, with the number chosen to be representative of the perceived heart rate at that effort level. If you took the rating on the Borg Scale and multiplied it by ten, it would get you an estimated heart rate. So, if you rated an activity with an RPE of 12, your heart rate would be around 120 beats per minute. In 1982 Borg added the CR10 (category ratio) scale, which gauged effort levels on a more straight forward 0-10 scale. 

Photo taken from: https://superfitandpregnant.wordpress.com/tag/borg-perceived-rate-of-exertion-scale/

After much use in the cardiac rehab world and aerobic conditioning world, Mike Tuchscherer of RTS training applied this concept to lifting, and a much simpler 0-10 scale was adopted. Mike Tuchscherer describes RPE as an assessment of your performance. Eric Helms and Mike Zordos have also taken this concept and created their spinoff known as RIR or reps in reserve. It is helpful for some to think in a strictly RPE manner (picture #1), whereas some prefer to think about it in the Reps in Reserve lens. We will be using the RPE scale in all our programming and throughout this article, but it is important to know that each RPE represents the following RIR:

RPE Described as Reps in Reserve

Photo taken from: https://legionathletics.com/wp-content/uploads/2018/05/rpe-rpi-scale.jpg

RPE and RIR are pretty much the same, and we use the terms interchangeably. The main difference would be how you wrote it out and what the number actually meant. For this article, we will stick with the RPE nomenclature. 

RPE vs. RIR

Photo taken from: @mack_canady

So how do you judge RPE?

Mike Tuchscherer has made this helpful chart to help us understand RPE

Photo taken from: https://articles.reactivetrainingsystems.com/2017/12/05/how-to-use-rpe-in-your-training-correctly/

When using RPE, anything below an RPE of 6 is considered a warm-up weight. For those of you that have done a meet, In terms of singles, another way to think about it is 7.5 is an opener 8.5 is a second attempt, and ten is your third. A .5 represents a maybe. An RPE of 8.5 would read as I could do one more rep, maybe two more. Another way to think about this is I could do one more rep, but probably could have still added more weight. 

There are a few things to keep in mind that I have found help a lot of people in understanding RPE: 

• You are really judging the last rep of the set. A 1@8 (read one rep at an RPE of 8) should feel like the last rep of a 5@8 (read 5 reps at an RPE of 8), but a 1@8 and a 5@8 will be different weights. Only the effort will be the same. 

• RPE is the same regardless of how many reps you do. If you do 400 lbs. x 1 rep and could only do one more, that is a 9. If you do 400x10 and could only do one more that is still a 9

• The same RPE is not going to be the same weight on any given day

• Do not gauge RPE mid-set 

• It is about the effort, not the weight. You must dissociate the weight on the bar from the RPE rating given 

Many people struggle to grasp RPE because it is a subjective measure, and lifting weights tends to be very objective, but the very subjectivity of RPE is what allows it to work so well. Because it is subjective, it allows for autoregulation (link last article) and for weight selection to be more accurate among a variety of different individuals. This also gives the coach and athlete a language to talk more accurately about how each set felt. If two people do a set of squats and give the exact same amount of effort (if there was an objective way to measure effort) and one perceived the set to be harder than the other. The one who perceived the set as harder will most likely accrue more fatigue. 

It is also important to note that RPE does not have to be perfect every single time. There are days you will overshoot your RPE and days you'll undershoot your RPE and, in the end, that usually averages out.

Derek Miles from Barbell Medicine made this graph to represent what it is like when someone first starts to use RPE.

Photo taken from: @derek_barbellmedicine on Instagram

When you first start training, those variances are going to be more pronounced, but as you get better at judging RPE, you will become more and more accurate. 

RPE is a skill 

So, we have mentioned a couple of times now that RPE is a skill that gets better with practice. But how do I go about doing that? First off, it is important to trust yourself. There are a bunch of studies out there that show we are pretty darn good at judging any set at an RPE of 7 or above even in an untrained population (Click here to read a few of those studies: 1, 2, and 3).

Some of the research even showed men on the leg press were accurate as far away from an RPE of 10 as an RPE of 5 (Click here to read). There has even been research showing you get better at judging RPE from one set to the next (Click here to read).  

We know that the farther you get from an RPE of 10 the less accurate we are at judging, but that is not a huge deal because mistakes at an RPE of 6 are not as detrimental as mistakes at an RPE of 9 since the absolute load and intensity are so much less. Since weights under an RPE of 5 are considered warm-up weights, it is really only necessary to be accurate in that 6-10 range. 

Second, RPE is a subjective measure. There is no right or wrong answer. This subjectiveness is useful because it takes into account psychological load. If you believe you could only do one more rep even if you could have done more, the stress is probably similar to someone who took their set to a place they could actually only do one more rep and believed they could only do one more rep. Our beliefs and expectations shape our reality. 

There are millions of factors that can affect your RPE on any given day and trying to track and make sense of all of it is impossible. Everything in your life can affect your performance on any given day. Here is just a small list of things that could affect your RPE: sleep, outside stressors, nutrition, hydration, motivation, beliefs about training, environment, and arousal (huge one). RPE takes all these factors into account and allows you to adjust your training accordingly. Arousal state can hugely affect RPE. A set you get all riled up for screaming, pumping your favorite song, etc. is going to feel much easier than a set you approach cool, calm, and collected. Mike Tuchscherer describes the best approach as follows: 

"RPE requires a bit of aggression. The best attitude to take is controlled-aggressive. If it was left up to you, you'd add a little more weight to the bar. You feel better when adding weight to the bar. But you're controlled enough to resist that urge if it's not a smart idea." -Mike Tuchescherer

Another way to practice the skill of RPE is through AMRAP (as many reps as possible) sets.  The use of AMRAP sets is known as "anchoring," and is used to establish if an individual is semi-accurate in previous RPE estimates. If you are assigned 10@7 (10 reps at an RPE of 7), and then the next set is assigned AMRAP, and you get 13 reps, you know you were accurate in judging your weight. Since an RPE 7 indicates you could do three more reps and you did ten reps that means on an AMRAP set (an RPE of 10), you should get 13 reps. If you get more than 13, you know you undershot your RPE; if you get less than 13, you know you overshot your RPE. 

You can also get better at judging RPE by paying particularly close attention to RPE when you are testing your one-rep max. As you build up, you will slowly get close and closer to an RPE of 10 and hopefully hit a true RPE of 10. This will give you a helpful reference point to refer back to. Knowing what a true 10 feels like is super important. 

Lastly, just practice. The more you do it, the better you get. As you start to use RPE more, you can learn your tendencies and become even more accurate. Some people get all hyped up and feeling good as they warm-up and always overshoot their RPE's whereas some people get nervous when the weight gets heavy and constantly undershoot their RPE. Knowing your tendencies will help you make better decisions when it comes to weight selection. 

Now we have looked at why we use RPE (link last weeks), what RPE is and how to get better at using RPE. Next week, we will go into what RPE is not, some common misconceptions surrounding RPE, pitfalls of RPE, and some general tips for applying RPE to your training. 

We will leave you with the RPE emoji chart, which seems to click with a lot of people!

Photo taken from: https://twitter.com/gemequestphysio/status/820553537260310529