Just getting started with a heart rate monitor and overwhelmed with all of the additional numbers? Maybe you're totally new to training and not sure about RPE? Here I will simplify the concepts and offer suggestions for what zones you should use, how to set them up, and how to use them most effectively.
This article will focus on RPE guidelines and physiological markers at certain intensities to keep you training in the correct zones, and will also explain heart rate zones and how to set them. It is important for all athletes no matter how high of a level to be intimate with the RPE scale, ultimately how you are actually feeling will dictate how hard you can or can't go, and it's very important for determining how you are recovering between workouts.
RPE or rate of perceived exertion is a scale of discomfort used almost universally throughout the world for medicine and hospital functions, athletic training, and research. Its purpose is to objectify a persons discomfort levels by assigning a number to a level of pain where 10 is the most pain you can endure and 1 is no effort or discomfort at all. There are a few different RPE models but I prefer to use the simple 1-10 scale because it is the most ubiquitous, easily understood, and most training programs like TrainingPeaks are designed to work with it.
No discomfort or exertion whatsoever.
Sitting or laying down
Minimal exertion and no discomfort
Slightly more exertion but still no discomfort
Very light jog, easy endurance intensity
Entirely comfortable but conscience of the effort needed
Regular jogging pace, endurance intensity. Should be able to breathe through your nose at a normal pace without feeling like you're choking
Discomfort begins and conscience of the effort
Still able to speak mostly normally, but needing to take deeper breathes to do so; tempo
Uncomfortable but bearable
High tempo-low threshold intensity
Uncomfortable and requires concentration
Breathing begins to pick up and it is difficult to speak in full sentences
Painful and requires significant focus
Only able to speak a few words at a time; max aerobic intensity
Painful, nearly all out
Quick and deep breathing, unable to speak more than a few words at a time; anaerobic intensity
Very painful, as hard as you can go
Max exertion sprint, last bit of an all-out max effort
An easy way to stay consistent with your RPE is to find something close to that intensity to anchor your thinking and focus to. This keeps you riding in the correct zone, and it gives you small things throughout the entire scale to look for so you can try and make your own personal RPE scale as consistent as possible to yourself.
This is generally the level you want to spend your time in when you are performing endurance rides to achieve the most benefit. A good reference to anchor yourself to here is when you get to 4, just before you go to 5, it should be at an intensity where you can breathe through your nose comfortably and normally. Many athletes think they can breathe through their nose at tempo intensities up in the 5-6 RPE range, but they are essentially hyperventilating. If you can breathe in such a way that it takes about 2 seconds to breathe in and 1.5 seconds to breathe out (this is a breath rate of 17 breaths per minute, normal resting breathing rates are typically 12-17 breaths per minute) then you are most likely riding at an RPE of 4 and at the best intensity for endurance riding.
This is the point where you will reach your anaerobic threshold, or FTP/ threshold heart rate. You can note this point because your breathing will suddenly and drastically start to pick up, at an RPE of 8 your breathing will begin to feel out of control but a 7 is just about the limit of what you feel like you are in control of. You will be breathing deeply and quickly, but not hyperventilating. When you are doing productive threshold work, this is the intensity you want to spend your time at.
What Makes RPE So Important?
Productive training will have to push your body to the limits sometimes, but most times you need to stay composed and maintain a set intensity as precisely as possible. Having this intimate knowledge of how your body feels throughout a range of intensities is important for metering your intensity later down the road. For example, you may know that once you get to an RPE of 8 you only have a few minutes before you are done and can't continue, so if you're going for a hard effort in a race, or going for a personal best, you will know that once you reach an 8 you'll need to back off slightly before you blow up entirely. Similarly, you may be out for a long endurance ride and you are becoming fatigued, now the power/ heart rate you had planned that was originally a 3-4 is now feeling like a 5-6. Having this knowledge and understanding of your own body will allow you to finish the ride without blowing up, maintain an intensity that is conducive for proper training, and keep you from accumulating so much fatigue you wont recover properly from it.
Upgrading from simply RPE to RPE and heart rate is possibly the best upgrade you can make in terms of your training tools. The amount of precision and accuracy a heart rate monitor adds will make your training even more productive and specific, as well as giving you access to new metrics to track your performance, recovery, and training as a whole.
Setting Up HR Zones for the First Time
If you just got a heart rate monitor and you have no idea at all where to start, basing your zones off an estimated max heart rate will be good enough until you accumulate enough data to perform tests and set your true zones.
Estimate Your Max HR
207- (your age)(0.7)
Calculate Your Zones
I like using the Basecamp Fitness Zones for Cycling for percent of max HR, I found it to line up most closely to the Joe Friel threshold zones which I think are the best zones for heart rate.
These zones will get you by for your first few months of training fairly well, but you should take notes of how you feel at the far high and low ends of each zone and make sure each respective heart rate zone corresponds with its related RPE rating from above. If these zones match the RPE chart well, these zones will work great for you, but if they seem quite off in places its best to get the testing done for a Joe Friel threshold based zones sooner than later to get more accurate zones.
Setting Your HR Zones with Data
After you've spent some time in the zones above, or you are eager to get your zones set more precisely, it's time to perform testing per Joe Friel's protocols to set your threshold heart rate and base your zones off that instead of your max HR. I prefer this method for a few reasons. Max HR can change quite drastically throughout a training block due to fatigue, hydration, nutrition, stimulants, etc. but threshold heart rate will remain almost entirely unchanged as you get more fit, fatigued or use stimulants. Another reason I prefer this method is that it is based off an estimation of the location of your anaerobic threshold, so your zones are based on a physiological process rather than an arbitrary percentage of your maximum.
Performing a Threshold Test
Joe Friel suggests performing a 30 minute time trial and taking the average HR for the final 20 minutes and making that your threshold heart rate. Make sure you warm up adequately for this test, I would recommend at least 20 minutes at roughly an easy endurance intensity, I also like to throw in an effort that is one or two minutes long at the intensity I intend to ride the test at. There are a few physiological reasons why this is important, but for less experienced athletes the shock it gives you mentally prepares you for the effort. Once you complete the test, the average heart rate for the final 20 minutes is your threshold heart rate.
I prefer the Joe Friel's Zones because it is specifically designed to be accurate at the anaerobic threshold, so it will be best at predicting intensities to work the metabolic processes involved in lactic acid production and clearance. Since the anaerobic threshold and the aerobic threshold are somewhat related to each other, I find these zones predict my aerobic threshold (endurance zone) very well too.
Why is Heart Rate The Most Important Training Metric
Although power is a more precise metric, I think heart rate may be the most important metric to look at when training, even if you have a power meter. As you get more fit, your threshold power will continue to increase but your threshold heart rate will not change much at all. For this reason, it is entirely possible (and I recommend it early in the year if you train with power) to ride to a prescribed heart rate and let the power fall where ever it may at that heart rate. Similarly, maximal aerobic gains are made most effectively at very high heart rates, not necessarily power outputs. These are all because heart rate is a Direct response to the metabolic processes occurring within the body, and through training we are trying to precisely target those specific processes in such a way that they get stronger or more efficient. If you are slowly getting stronger over time and not testing your FTP often enough, you will get to a point where your heart rate will be lower than it once was at the same power, but since your heart rate is lower, you are not likely stressing those processes as effectively as you could be. If you rode to a prescribed heart rate instead, you will always be riding at that intensity that elicits the most effective response and the power will follow.
Interested in trying a plan that puts all of this into practice? Check out my Intro to Structured Training plan on TrainingPeaks. Gain fitness while learning firsthand how these principles work in real life.