CrossFit: Understanding Rate of Perceived Exertion (RPE) for Training

What does RPE stand for CrossFit?

In CrossFit, RPE stands for Rate of Perceived Exertion, a subjective scale used to quantify the intensity of an exercise or an entire workout based on how hard you feel you are working.

Understanding RPE: The Basics

The Rate of Perceived Exertion (RPE) is a widely recognized tool in exercise physiology, initially popularized by Gunnar Borg in the 1960s and 70s. It provides a means to measure the subjective intensity of physical activity, offering a valuable alternative or complement to objective measures like heart rate or a percentage of one-repetition maximum (1RM). Unlike these objective metrics, RPE accounts for the holistic physiological and psychological stress an individual experiences during exercise, including factors like fatigue, pain, and mental effort.

While Borg's original scale ranged from 6 to 20, a modified 0-10 RPE scale has become more prevalent in modern strength and conditioning, including its application within the CrossFit methodology. This scale assigns a numerical value to your effort level, where 0 represents no exertion at all, and 10 signifies maximal effort – the absolute hardest you could possibly work.

RPE in the CrossFit Context

CrossFit is characterized by its "constantly varied, high-intensity, functional movements." This inherent variability, coupled with the often-complex nature of its workouts (WODs) that combine strength, gymnastics, and metabolic conditioning, makes RPE a particularly useful tool.

In a CrossFit setting, RPE isn't just about how heavy a barbell feels; it encompasses the overall demand of a workout. For instance, an RPE of 8 in a strength session might mean lifting a weight that leaves you with two good reps in the tank. The same RPE of 8 in a conditioning WOD, however, would describe the feeling of pushing hard but maintaining a sustainable pace, knowing you couldn't go much faster for the duration, yet still capable of completing all prescribed reps.

Key applications of RPE in CrossFit include:

• Autoregulation: Adjusting daily training loads based on how an athlete feels on a given day, accounting for factors like sleep, stress, and recovery.
• Skill Acquisition: Guiding effort levels for complex movements, ensuring technique isn't sacrificed for speed or load.
• Conditioning Pacing: Helping athletes learn to pace themselves effectively in WODs to maintain intensity without burning out prematurely.

The RPE Scale: A Closer Look

The most common RPE scale used in contemporary training, including CrossFit, is the 0-10 scale. Here's a breakdown of what each level generally represents:

• 0 - No Exertion: Sitting, resting, no effort.
• 1 - Very Light Exertion: Minimal effort, barely noticeable.
• 2 - Light Exertion: Easy, can maintain for hours, breathing easy.
• 3 - Moderate Exertion: Still comfortable, but aware you're exercising.
• 4 - Somewhat Hard: Starting to feel challenged, breathing more heavily.
• 5 - Hard: Noticeably challenging, can still hold a conversation, but with effort.
• 6 - Hard to Very Hard: Difficult, short phrases only, pushing your comfort zone.
• 7 - Very Hard: Max effort for longer durations, conversation is difficult, nearing your limit.
• 8 - Extremely Hard: Very challenging, can only speak a word or two, could maybe do 2-3 more reps if forced (or maintain pace for very short bursts). This is often the target for heavy lifting days.
• 9 - Near Maximal Exertion: Extremely difficult, could maybe do 1 more rep if absolutely forced (or maintain pace for only a few more seconds).
• 10 - Maximal Exertion: All-out effort, no reps left, cannot go any harder, complete exhaustion.

How to Accurately Apply RPE in Your Training

Developing an accurate sense of RPE is a skill that improves with practice and self-awareness.

• Self-Assessment: After each set or at key points in a WOD, take a moment to honestly evaluate your effort. Ask yourself: "How many more good quality reps could I have performed?" or "Could I have maintained this pace for significantly longer?"
• Practice and Consistency: Regularly incorporating RPE into your training will help you calibrate your internal scale. Over time, your perception will become more consistent and reliable.
• Considerations: Your RPE for a given weight or pace can fluctuate daily based on factors like sleep quality, stress levels, nutrition, and recovery. RPE allows you to adapt to these daily variations.
• Beyond Just Weight: Apply RPE not only to strength components but also to gymnastics (e.g., how hard was that set of muscle-ups?) and conditioning (e.g., how sustainable was that pace on the rower?).

Benefits of Using RPE in CrossFit

Integrating RPE into your CrossFit training offers several significant advantages:

• Autoregulation: RPE empowers you to adjust your training based on your body's daily readiness. If you're feeling fatigued, an RPE-based prescription allows you to safely reduce the load or intensity, preventing overtraining. Conversely, on days you feel exceptionally strong, you can push a bit harder.
• Injury Prevention: By listening to your body and moderating effort when needed, RPE can help prevent pushing through excessive fatigue or pain, reducing the risk of injury.
• Enhanced Performance: Smarter training leads to better recovery and, ultimately, more consistent progress. RPE helps optimize the balance between stimulus and recovery.
• Improved Body Awareness: Using RPE cultivates a deeper connection between your mind and body. This heightened interoception is invaluable for long-term athletic development and overall well-being.
• Flexibility: RPE is particularly useful in CrossFit's varied programming, where prescribing exact percentages might be impractical for diverse movements or highly fatiguing WODs.

RPE vs. RIR (Reps in Reserve)

While often used interchangeably or together, RPE and Reps in Reserve (RIR) are distinct but related concepts.

• RIR specifically refers to the number of additional reps you could have performed with good technique after completing a set. For example, 2 RIR means you could have done 2 more reps.
• RPE is a broader subjective measure of overall effort or how hard it felt.

There's a strong correlation: an RPE of 8 often corresponds to 2 RIR, an RPE of 9 to 1 RIR, and an RPE of 10 to 0 RIR. Many coaches will use RIR to help athletes calibrate their RPE for strength work, as it provides a more concrete anchor. However, RPE remains more versatile for conditioning and mixed-modality workouts where "reps in reserve" might not be a direct or easily quantifiable metric.

Limitations and When to Use Other Metrics

While powerful, RPE isn't a perfect system and has some limitations:

• Subjectivity: Its greatest strength is also its potential weakness. An individual's perception of effort can vary, especially for beginners who haven't yet learned to accurately gauge their limits.
• Newcomer Challenges: Novice athletes may struggle to differentiate between an RPE 7 and an RPE 9, often underestimating or overestimating their true effort.
• Context Dependence: RPE for a single heavy lift is different from RPE for a high-rep, light-weight conditioning piece. Learning to apply it accurately across different modalities takes time.
• When Objective Metrics are Better: For specific phases of training, such as peaking for a competition or precise strength cycles, objective metrics like percentages of 1RM, specific time domains, or strict rep schemes may still be necessary to ensure specific physiological adaptations.

Conclusion: Empowering Your CrossFit Journey

Understanding and effectively utilizing RPE is a fundamental skill for any serious CrossFit athlete or coach. It transforms training from a rigid, prescriptive endeavor into a dynamic, responsive process that adapts to your body's daily demands. By mastering the art of perceived exertion, you gain a powerful tool for autoregulation, injury prevention, and ultimately, a more intelligent and sustainable path to achieving your full potential in CrossFit and beyond. Embrace RPE, listen to your body, and empower your performance.