When it comes to using Rate of Perceived Exertion (RPE) the #1 question is, “How do you feel?” How does this interval feel? How hard are you climbing? How did that long ride feel? How hard was that workout? How do you feel? It is an essential question—possibly the most important question—asked by any coach of any athlete.
For all of the technology we have available—heart rate monitors, activity/sleep trackers, power meters, heart rate variability, food tracking apps—nothing can tell you how you feel except you. You’re the culmination of millions of years of research & development, and recognizing how you feel is a crucial piece of data for any athlete following any plan in pursuit of any goal.
The RPE scale, also known as the Borg Scale, is a way of measuring how hard you’re working. It allows you to subjectively rate your level of exertion during exercise. There are two versions of the RPE scale, the original and the revised scale. The original RPE scale is scaled from 6-20. Why the odd range? It was designed with a healthy young adult in mind. Multiply any of the numbers by 10 and you get a heart rate that matches approximately to the exertion level listed on the chart. For example, Let’s say you do an interval at a heart rate of 150 beats per minute (bpm). 150/10 = 15. Therefore, 150 matches up to 15, a “hard” effort, on the Borg Scale. Does that feel right to you? (For me personally, 150 bpm is definitely hard work.) It’s not pinpoint accurate for everyone, but it gives you a starting point to match heart rate to exertion.
Reddiyo uses the Revised Scale (below) that uses the values 1-10, which is easier to comprehend for many people compared to the 6-20 scale. The concept is the same though. Significant research has gone into the RPE scale. RPE correlates well to heart rate changes and it’s been tested in different exercise situations and different populations. It works well in helping you measure changes in your workload and it turns out that you’re very good at gauging how hard you’re working.
Reddiyo uses RPE for several reasons. We use heart rate and/or power in prescribing a particular workload, but we need that workload to be appropriate to your abilities. RPE helps with that calibration. For example, your workout might include a four minute interval in zone 4 (RPE 4-5). If you are unable to complete the four minutes and blow up two minutes in, then the RPE was much higher than a 4 or 5 and inappropriate for your abilities that day. It is likely an indication that you need to rest. Perhaps you have not been getting enough sleep or have a cold coming on. Maybe you pushed a little too hard in your previous workout and need more recovery. Likewise, if the four minute interval feels too easy and you were able to complete it while having a full blown conversation, that suggests gains in fitness. Using RPE will help you tune into those situations. If workouts are consistently too hard or too easy Reddiyo will likely spot that in your training data and make recommendations for training plan adjustments to avoid undertraining/overtraining.
It's very important to use RPE with your easy workouts. Low-intensity, easy efforts at 2-3.5 are crucial for endurance athletes. Recovery rides and base training (aka long, slow distance, or LSD training) takes place at this easy intensity. The purpose of easy workouts is to strengthen your aerobic energy system and build new mitochondria, the power generators of your cells. Mitochondria provide energy for all long-duration activities. If you work too hard, you deemphasize your aerobic energy system in favor of other systems and you avoid the rest your body needs to prepare for the next hard workout. Recovery rides and runs, therefore, are deliberately easy. Long rides and runs may indeed be difficult, but the difficulty should come from the duration of the workout, not from any sprint- or interval-type effort. It's important to use RPE to make sure your easy workouts are actually easy.
Reddiyo uses RPE to train you effectively, keep you safe, and keep you motivated. Many workout fads and advertising would have you believe that you should push yourself to the extreme and “go hard or go home.” That’s great for selling stuff but it doesn’t reflect effective training. Working too hard, too often will burn you out and expose you to injury. Your nervous system will tolerate only so much high-intensity, orange- and red-zone work. In fact, a common sign of overtraining is for a familiar ride or workout starts to feel harder than normal. If this happens then it’s time to back off a little, rest, and do some easy work. Remember, Harder! Harder! Harder! isn’t better. If that were the case then sprinting all-out from the start would win a marathon.
Lastly, good athletes listen to their bodies. Reddiyo uses RPE to help you tune in and listen to what you’re body is telling you. After each workout be sure to enter feedback (tap the pencil icon on the lower right of the workout results screen). This subjective data is just as important as the objective data your device tracks for you so be sure to enter your feedback consistently.
Using RPE helps you dial in your training. It is an important skill that involves awareness and deliberate focus. Use it consistently to get the most out of your training.