What is RPE in strength training — and how to use it
RPE is a 1-10 scale of how hard a set felt. Used right, it makes your program respond to real-world performance — not pretend you're always 100%.
The scale explained
In resistance training, RPE is often paired with estimated reps in reserve (RIR): RPE 10 usually means no additional repetition was available, RPE 9 roughly one rep remained, and RPE 8 roughly two. These are practical estimates, not precise physiological measurements.
Why RPE beats percentages
Percentage-based loading and RPE answer different questions. Percentages anchor load to a tested maximum; RPE records how difficult the completed set felt. Using both can help interpret performance without pretending that one subjective rating measures readiness by itself.
How to estimate accurately
Beginners over-rate RPE. Track for 4-6 weeks; you'll calibrate. AJYX learns your RPE patterns over time.
How AJYX uses RPE
Every set you log includes optional RPE. AJYX uses it to adjust the next session's load — exactly what a coach would do.