Many different online training platforms and apps now allow you to provide information about “how you felt” and “how hard you worked” during your last session. This is known as a rating of perceived exertion (RPE).

From my perspective, as an ASICS FrontRunner, qualified Athletics coach, and Sport and Health Sciences PhD student, being able to regularly self-report RPE can make a positive difference to your training, regardless of your performance level. It provides an extremely simple way to see how your training is going, while allowing your coach to evaluate how you are coping with the sessions. Also, for those of you who want to gain a better understanding of your performance (data geeks!), I would like to suggest that you go one step further and calculate session rating of perceived exertion (sRPE), as a measure of internal training load (ITL).

What is Training Load?

Improvements in performance can be achieved by carefully modifying different training load parameters. These parameters include intensity, duration, and volume, each of which can be altered during a training cycle to ensure that your performance is suitable for your phase of training. Said in a different way, training load can be manipulated to accomplish a desired training response. When monitoring your training load, the units of measurement can either be categorised as “external” or “internal.”

External training load (ETL) refers to the total amount of work that you, as an athlete, complete during a training session. ETL is determined by the organisation, quality, and quantity of your training, and is how a coach often prescribes training. An example of ETL is the total distance that you cover during a training session. Based on this ETL, the relative physiological, psychological, and biomechanical stress that is imposed on you can be calculated – reflecting your ITL. An example of ITL is the use of different heart rate data recorded during your training session, such as the total time spent in heart rate zones.

As you may have already noticed, ETL is much easier to measure when compared to ITL. For example, ITL is usually measured using heart rate, requiring access to a heart rate monitor. However, ITL and ETL are both as important as each other when it comes to improving your performance and preventing adverse training outcomes. As a result, sRPE has been established as an effective measure of sRPE across many different sports, including distance running.

How to Calculate sRPE:

sRPE = Rating of Perceived Exertion x Total Session Duration

sRPE is calculated by multiplying the duration of your training session (in minutes) by your self-reported RPE (“how hard you worked”), as reported by the following 10-point scale:

This scale, known as a category ratio scale (CR10), translates your perception of effort (i.e., ‘somewhat hard’) into a number. When self-reporting your RPE, it is advised that you should wait until thirty minutes after you have completed your training session. This self-reported RPE should also factor in your warm-up and cool-down, so do try to delay self-reporting RPE until thirty minutes after your cool-down.

As an example, imagine that you have just smashed a 3 x 10min (3min jog recovery) session, as recommended by Holly Rush. When including a warm-up and cool-down, this session would last for sixty minutes. After this training session, when answering the question “how hard was your session?”, you might decide to self-report an RPE of 7 (‘very hard’). Therefore, all you need to do is multiply 60 by 7, giving you an sRPE of 420.

This number is recorded as an arbitrary unit (AU). The higher the AU, the more relative physiological and psychological stress you have endured during the training session. When recorded on a daily basis, you can calculate a weekly sRPE score by adding all of the individual sRPE scores together.

Why use sRPE to Measure Internal Training Load?

The primary use of sRPE is to provide you with an overview of how your training load changes over time. This is especially useful if you don’t have access to the heart rate and power tools that are required to calculate other measures of ITL. 

Importantly, tracking sRPE is a simple way to monitor your progress during a training programme. For example, as you put in a consistent block of training, you may start to notice that your sRPE values are reducing during tempo runs. This allows you to see a tangible improvement in performance and adjust your training accordingly. Tracking sRPE may also allow you to notice when you are a little under the weather or starting to ‘overtrain,’ allowing you to adapt your training plan before the situation gets worse. While not included in this blog, sRPE can also be used to calculate other variables, such as training monotony and strain.

So, why not give recording sRPE a go? It costs nothing and could prevent adverse training outcomes... win-win!