Understanding RPE and RIR in Strength Training

Monitoring effort during weightlifting is essential for progress and avoiding overtraining. Two popular tools for this are Rate of Perceived Exertion (RPE) and Reps in Reserve (RIR). While similar, each has unique strengths and applications for different training styles.

What is RPE?

RPE uses a 1-10 scale to measure intensity:

• 1-3: Very light effort (warm-ups/recovery).

• 4-6: Moderate effort (endurance/hypertrophy). Feels easy to sustain and doesn’t cause significant fatigue.

• 7-8: Challenging but sustainable (hypertrophy/volume). Requires focus but allows for consistent performance across sets.

• 9-10: Near or maximum effort (strength/peaking). Demands maximum focus and energy, often used for testing limits or PR attempts.

What is RIR?

RIR estimates how many reps you have left before failure:

• 3 RIR: Three reps left (moderate effort). Ideal for warm-ups or lower-intensity volume work.

• 1 RIR: One rep left (high intensity). Pushes you near your limits without hitting failure.

• 0 RIR: Failure (maximum effort). Used sparingly as it’s highly taxing on the body.

RIR often correlates with RPE, where RPE 8 roughly equals 2 RIR. Both systems rely on self-awareness and experience to use effectively.

RPE/RIR for Different Training Styles

• Hypertrophy Training: RPE 7-9 or 1-3 RIR. This range balances volume and intensity for muscle growth by working close enough to failure to stimulate the muscles without overfatiguing.

• Strength Training: RPE 8-10 or 0-2 RIR. Higher intensity targets maximal force output, ideal for low-rep, high-weight sets.

• Endurance/Recovery Work: RPE 4-6 or 3-5 RIR. Focuses on lower effort to improve muscular endurance, reinforce technique, or promote recovery between intense sessions.

Integrating RPE and RIR

Combine both systems for optimal results. For example, program a session as “3 sets at RPE 8 (about 2 RIR)” to target a specific effort level while leaving some energy in reserve for subsequent sets. Alternatively, gradually reduce RIR over a training block (e.g., starting at 3 RIR and progressing to 1 RIR) to ensure progressive overload.

Final Thoughts

Both RPE and RIR are valuable tools for self-regulating intensity. RPE provides a broader perspective on effort, while RIR offers precision in gauging proximity to failure. Use them strategically to match your training goals, whether building strength, hypertrophy, or endurance, and enhance your ability to train effectively and safely.