You are serious about making progress in your training. You know that tracking your workouts is essential. But what exactly do you measure? And – what should you?
When it comes to running, most of us note down mileage and pace. If you are ambitious – or just a data geek like me – you might also track your heart rate.
But what about perceived effort? Do you ever track how hard the workout felt? You should.
And in this article, you will learn why and how.
Why Measure Effort?
Before we get into the details about measuring a training session’s effort, let’s take a step back and ask ourselves why we even want to do this.
Imagine you are following a training plan for your next marathon. Long runs, sprint sessions, off-days, goal paces – everything is neatly laid out for you. Maybe the program even specifies the heart rate zones you should be aiming for.
No matter if you developed the plan yourself, got it from a coach, or your favorite running magazine – there is one thing missing. And that is your specific stress level and how hard the workout feels to you.
Why does this matter?
Well, because by tracking how hard the prescribed workouts feel, you have more flexibility to adjust your training plan. When you feel “off,” you take it easy. When you feel like a million bucks, you up the intensity.
You respect your body’s ability to follow the defined training plan. Hence you can make sure you get the most out of every training session.
And how do you track how the workout feels? Let me introduce you to the “Rate of Perceived Exertion.”
What Is The Rate Of Perceived Exertion And How Do You Use It?
Dr. Gunnar Borg did the pioneering work regarding the rate of perceived exertion and developed the first scale. It was a 6-20 scale and designed to measure the effort of endurance exercise.
This scale corresponds roughly with heart rate. Multiply the Borg scale rating by ten, and you have the corresponding heart rate. At rest, your heart rate is approximately 60 – which corresponds with the lowest number on the scale. When you are giving a sprint your best effort, your heart rate might hit 200 – your perceived exertion on the Borg scale is 20.
Borg later modified the scale so that it ranged from 0-10. This 1-10 scale is now commonly known as the Borg CR-10 scale and is usually referred to when people talk about RPE. Below you can see a side-by-side comparison of the two rankings and verbal descriptions of the corresponding ratings.
While you could use the Borg scale, I recommend that you get used using the CR-10 scale for two reasons.
First, it is also used in strength training to define the intensity of single exercises. Second, the CR-10 scale is the basis for calculating your workout’s overall training load – the session RPE.
I will write more about using RPE during your strength training sessions in another article. For now, let’s focus on session RPE, what it is, and why using it will improve your training.
What Is Session RPE?
Once you are familiar with RPE’s concept, you can use it to calculate session RPE – a simple measure to assess training load over several training sessions.
Session RPE is simply the product of RPE and the duration of your run (in minutes).
Foster proposed this method to measure training load, and it is a tool you can use for all your different activities. Use it for your running and your strength training plans. And if you are into Crossfit or Bootcamp style workouts, then yes, use it for those too.
Several studies have shown that session RPE is a useful tool for successfully assessing training load in various activities. And a review study by Haddad et al. (2017) confirmed that session RPE is a valid and reliable tool for measuring training load for a variety of different activities.
Hence I advise you to use it for all the other activities you have on your schedule and not only for your running sessions. That way, you can calculate your overall training load across various activities.
The only difference between strength training sessions and other workouts is that you multiply your RPE with the total number of repetitions for your lifting sessions. For all other workouts, you multiply your RPE with the activity duration (in minutes).
How Can You Use Session RPE In Your Training?
Now that you understand the RPE scale and the concept of session RPE, you might be wondering how you can use it in your training.
I suggest you follow these steps:
1. Get Used To The RPE scale
Start by assigning a rating of the effort you felt for each workout you completed.
Let’s assume the training plan you follow calls for a run of 50-60 minutes. After you finished, you add in your training log how hard the run felt.
You should also add anything that is going on in your life that you think might impact your workout. Examples could be lack of sleep, a new project at work that is stressing you out, a fight with your spouse, or a vacation.
Don’t worry about “getting it right” when you use the RPE ratings. Refer back to the scale and descriptions every time you need a refresher.
Over time you will become better at tuning in to your body and using the scale.
2. Monitor Your RPE Ratings
I suggest you track your RPE ratings for at least 4-8 weeks. Then take some time where you go back in your training logs and review your RPE ratings.
You might notice that you rate the same workout with different RPE’s.
This is awesome.
If you noted down your stress levels and the cause of the stress, you can now use it to assess how work stress, problems with your spouse, or lack of sleep affect your training sessions.
For example, let’s say you have a 5km run scheduled once a week. One week, you rate it with an RPE of 5, and in the week after, you give it an RPE of 8.
You wonder why the same workout felt so different in those two weeks.
You think back to the first week. You were on vacation, got enough sleep every night, and your spouse surprised you with a romantic dinner the night before. This week, however, your boss surprised you by assigning you a new project, and your new neighbors are nocturnal party animals.
This example shows how using session RPE can help you understand your body’s response to stressors other than training.
3. Use RPE To Predefine The Intensity Of Your Workouts
Once you feel comfortable using the RPE scale, you can begin to use session RPE as a tool to design your training program.
That means you decide in advance how hard each of your workouts should feel. That way, you can make sure your easy runs are really easy, and your hard runs are, in fact, hard.
Besides, RPE is a great tool to see if your fitness level is improving.
For example, let’s say you schedule your weekly 10km run with a session RPE of six. In week one, you run the 10km in 68 minutes. After three months of training, you run the 10km with the goal RPE of six in 64 minutes.
Of course, two data points are not enough to make the definitive claim that you have improved your fitness.
It could be that one day you were more rested than the other. As always, you have to look at the long term trend. However, if the long-term trend shows that you reduce your 10k time while staying at your goal RPE, you can indeed claim that your fitness did improve.
4. Use Session RPE To Track Training Load
Finally, you can use the session RPE to track your training load.
If you remember, you need to multiply your RPE with the time (in minutes) of your run, to calculate your training load. On your rest days, you add a 0 as session RPE for that day.
By doing this over more extended periods (weeks, months, a specific training cycle), you will gather valuable data. For example, you can assess if your easy weeks were really easy or more challenging than anticipated.
Let’s say you had a recovery week with reduced mileage planned. However, due to a new project at work, you were severely sleep-deprived. Every workout felt “really hard” – a seven on the RPE scale.
You calculate the training load and discover that your training load was similar to that of the week before. Despite reduced training volume. You decide to run even less the next week to ensure you have had your recovery week.
This example shows that session RPE is an excellent tool to use when you want to make sure that your training is individualized and takes your specific life circumstances into account.
Tracking your workouts is essential if you want to make sure you are making progress towards achieving your fitness goals.
While objective measures, such as mileage, duration of your run, or pace, form the basis of any training plan, they are not enough.
Your stress response is an essential factor you need to consider.
You want to make sure you push yourself hard enough when you are well recovered and back off when your mind or body is exhausted.
Only then will you progress as rapidly as you can and make sure you avoid periods of overreaching that are too long or even drift into overtraining. Use session RPE to measure your workouts’ intensity, and use it to plan your training for better long-term progress.