Rate of Perceived Exertion (RPE) - An Alternative To Percentages

In the context of strength training, Rate of Perceived Exertion (RPE) is a tool that measures the difficulty of your previous set. The RPE scale was originally developed for cardiovascular research, but in recent years it has become a popular tool for prescribing intensity in strength training programs. This is in large part due to the work of Mike Tuchscherer (Reactive Training Systems), who adapted the RPE scale for use in Powerlifting:

Source: https://articles.reactivetrainingsystems.com/2015/11/29/beginning-rts/

The goal of this scale is to gauge the difficulty of a set relative to your maximum effort (the hardest set you could perform while still completing the final rep). The scale starts at 5.5 because sets below RPE 5 are usually too difficult to rate accurately. These sets are also so light that they won't constitute a working set. Anything below RPE 5 is a warm-up set.

I like to prescribe RPE targets in many of the programs that I write and I'll often use RPE in class to communicate the intended intensity of strength sessions as well. When implemented correctly, RPE helps to provide more precise communication about the intended (and actual) difficulty of training. Prescribing "a heavy set of 3" is more vague than "a set of 3 @ 9 RPE". In the first case, it's unclear to the athlete exactly what "heavy" is intended to mean.

You may be wondering, if precision is the goal why not prescribe an exact percentage? One advantage that RPE has over percentage-based training is that RPE allows the athlete to auto-regulate training load. Your readiness to train will fluctuate from day to day. Imagine you had a poor night's sleep, followed by a particularly stressful day at work, and you haven't eaten nearly enough to properly fuel your training session. Now imagine the opposite situation, you are well-rested, your nutrition and sleep have been better than usual and work has been going great. Your training experience on those two hypothetical days will be very different and using an RPE target allows you to apply an appropriate load to the bar to match the intended stimulus on the day. Throughout a program, this can make a big difference. RPE allows an athlete to adapt the program to take advantage of times when strength gains are coming faster than expected, or times when the rate of progress is slower than expected. In my experience, a program rarely goes perfectly to plan as outside factors always influence what goes on in the gym (both positively and negatively), so having this flexibility is beneficial for a lot of people.

RPE is also useful when you don't know an accurate 1RM for a given exercise. For example, I'm a big fan of programming tempo and pause work. It is difficult to put an exact percentage on a back squat set with a 5 3 X 1 tempo. However, using RPE allows me to communicate the desired intensity for that set. The same is true for supplemental and accessory exercises, for which we typically won't test 1RMs.

Although I am a fan of using RPE, it's not for everyone. Beginners will have a difficult time accurately rating RPE. New lifters typically won't have an accurate reference to what a true max effort set is, so it is difficult for them to consistently measure RPE. Like any other lifting skill, RPE needs to be developed over time, but In my experience, RPE is unnecessary (and typically inaccurate) for beginners. It's best for those lifters to focus on making technical improvements and incrementally adding weight to the bar or reps to their sets each time they lift. A lot of progress can be made with that basic approach.

RPE also requires some familiarity with the lift for the athlete to gauge it correctly. Even an intermediate or advanced athlete will need to learn the new movement and become comfortable with it before they will be able to effectively use RPE. Furthermore, for RPE to function correctly the lifter needs a target weight in mind for the session. Otherwise, they may overshoot their RPE target and miss reps, or they may expend so much energy on unnecessary warm-up sets that their top set for the day is substantially lighter than it should have been. In this case, having experience with the movement will help the lifter to plan for their expected top set. When possible, providing a target percentage range along with RPE is a useful strategy in this scenario.

Before implementing RPE fully, a beginner lifter (or someone who has never used RPE before) should start by simply rating their RPE post set with no bearing on the next set or their weight selection. At this point, the purpose of rating RPE is strictly to begin developing the skill and awareness needed to accurately use RPE in the future. As stated above, the lifter should be focused on progressing by making technical improvements, and by adding weight to the bar or reps to their working sets each time they lift until they are no longer able to make progress with a linear periodization approach. In my experience, a simpler approach is often more effective for newer lifters. Adding more complexity to a program too soon can make the training confusing and/or intimidating for a lot of new lifters.

If a lifter is extremely motivated and aggressive with their training, RPE may not be a useful tool. For RPE to work correctly, the lifter must be aggressive enough to want to continue adding weight to the bar, but mature enough to stop themselves when they know they've met the intended intensity. Some lifters will consistently overshoot their RPE targets due to their strong motivation to lift more or work harder for each session. For these athletes, prescribing a percentage with or instead of RPE may be more effective in the long run. Similarly, with lifters who consistently undershoot their targets or who are not confident enough to continue increasing weight on a given lift, prescribing a percentage or a specific weight is may be more effective.

RPE is not an excuse to take it easy or to avoid adding weight to the bar. RPE is simply a tool that tries to add some objectivity to the subjective training experience of an athlete, so that the coach and lifter may communicate more effectively about the intention of the programming, the execution by the athlete, and the effect. I have found it to be a useful tool for many of the people that I've worked with. However, RPE is not for everyone and there are many ways to get strong. In some cases, RPE may an appropriate tool for the job, but in others, it can cause more frustration than benefit.

In the long run, RPE is a great way for many lifters to learn how to train using auto-regulation. Rather than making program changes by 'feel' using RPE provides a framework for lifters to adapt their programming on the fly, based on how their training is going and what their life is like outside the gym. This allows the lifter to take advantage of great training days and to dial back on 'off' days so that one off day doesn't become an off week or month. Over the long run, I believe that this helps to create more autonomy for the lifter and a more engaging training experience overall.