When exercising, it's important to monitor your intensity to make sure you're working at a pace that is challenging enough to help you reach your goals, but not so hard that you blow a lung. One way to do that is to use a Perceived Exertion Scale. It's often abbreviated as RPE—rating of perceived exertion. The standard scale that you will often see is the Borg Scale of Perceived Exertion, which ranges from 0-20. RPE is a good way to monitor your fatigue levels during workouts.
A Simpler RPE Scale
For the workouts designed in Warrior, we use a simpler perceived exertion scale (RPE). You will see it listed next to exercise intervals in every session. It's a little easier to remember as it only goes from zero to ten rather than the 20-point Borg Scale.
When you are exercising, ask yourself how comfortable you are, how hard you are breathing and how much sweat-effort you feel like you are expending. How easily you can talk, known as the talk test, factors into this scale and is a quick way to gauge effort.
RPE Levels of Perceived Exertion
- Level 1: I'm watching TV and eating bonbons
- Level 2: I'm comfortable and could maintain this pace all day long
- Level 3: I'm still comfortable, but am breathing a bit harder
- Level 4: I'm sweating a little, but feel good and can carry on a conversation effortlessly
- Level 5: I'm just above comfortable, am sweating more and can still talk easily
- Level 6: I can still talk, but am slightly breathless
- Level 7: I can still talk, but I don't really want to. I'm sweating like a pig
- Level 8: I can grunt in response to your questions and can only keep this pace for a short time period
- Level 9: I am probably going to die
- Level 10: I am dead
In general, for most workouts, you want to be at around Level 5-6. If you're doing interval training, you want your recovery to be around a 4-5 and your intensity blasts to be at around 8-9. Working at a level 10 isn't recommended for most workouts. For longer, slower workouts, keep your PE at Level 5 or lower. As a general rule of thumb, if you rate a session as an 8 or higher, hold back for a day or two before hitting another hard session. Ultimately, if you were to plot your RPEs on a chart, there should be consistent ups and downs over time.
Correlating Heart Rate and Perceived Exertion Levels
Measuring your heart rate is the more precise way to determine if you are in the moderate-intensity or vigorous-intensity exercise zones. But you may not always want to wear a heart rate monitor chest strap, which is the most accurate way to measure it. Use a heart rate monitor and note how you feel at different target heart rates. Then you can draw a correlation with the RPE scale and leave the monitor behind. Occasional workouts with the heart rate monitor will help keep you on track.
The grip heart rate sensors on cardio machines and heart rate sensors on wearables like the Fitbit and the Apple Watch are less accurate than a chest strap heart rate monitor.
But you can also see how they compare to your RPE and use them as a check. By calibrating your RPE to your heart rate, you won't have to rely on a device to know when to speed up or slow down or increase the incline or resistance.
As an athlete, your goal is continuous, sustainable improvement. Be honest when you feel you may be veering into overtraining. If you do your own program, allow yourself a couple days off and see if your symptoms improve. If you are doing Warrior workouts, be up front about your symptoms and consider scaling things back for a bit.