RIR and RPE in Periodization Training: Meaning, Benefits, How to Use

RIR (reps in reserve) and RPE (rated perceived exertion) are the most accurate ways to gauge your workout intensity during strength training, hypertrophy, periodization, or general fitness.

Let’s cover them all in this blog, from understanding their meaning and benefits to effectively using them in your training. This blog is written by Patryk Piekarczyk, MS, CSCS, ACSM-CPT, a fitness and nutrition coach with years of experience.

RPE means Rating of Perceived Exertion, a Borg Scale (from 1 to 10 or 6-20) that rates the intensity of physical activity corresponding to their mental fatigue and strength.

Simply put, RPE helps track how hard your body works to finish a set, a rep, or an activity. Each number corresponded with a multiple of 10 and was associated with heart rate. For example, an RPE 8 would be a heart rate of 80 beats per minute. 

Since heart rate is a less relevant metric for lifting, a scale of 1 to 10 is typically used. Thus, a 1 out of 10 is the lowest rating, and a 10 is the maximal effort. Here’s a breakdown of the RPE scale:

Typically, 6 is the lowest rating for RPE when used for lifting. Therefore, it becomes difficult to estimate RPE under 6 accurately, and for strength or hypertrophy purposes, sets performed under an RPE of 6 aren’t very effective.

But if you are trying to increase speed or power, sets under an RPE of 6 would be helpful. For this case, converting RPE to a percentage of 1RM (1 rep max) might work better. The easiest formula is multiplying your RPE by 10, or you can use this RPE Calculator and Converter for more accuracy.

If you’re interested in how you can implement other online personal training periodization methods, such as percentages, check out this article.