Rate of Perceived Exertion
Old school runners love telling newcomers that all they need to do is to “run more miles at a lower RPE, and sprinkle in some higher RPE days”, then vanish into the sunset.
Most times, this leaves the new runner dazed and confused, unsure of what was said at all. Then they go off and run to what they think is a low rate of perceived exertion (RPE). This is where the problems occur. What you think a low RPE is most likely a medium-to-high RPE. And that’s okay for now.
In order to use RPE correctly, you need hands on experience running, the ability to interpret your training data, and be able to process the “feel” your body is giving you.
Understand what your levels of RPE are on a normal day, based on past training data and “feel”.
Be able to apply RPE accurately when environments change, training loads increase, or different parts of a run call for exertion fluctuations.
I am big on weaponizing data for training, but I still love to leave room for the subjective. Being able to marry the objective data with your subjective feel is a powerful skill. It takes understanding the data, experience of working in different RPE/zones, along with a realistic view of what is going on around you (environmental stressors).