The PRE Scale or Perceived Rate of Exertion is a simple scale where you, as the participant assigns a number between 1 and 10 based on how intense the activity feels to you at the time.
In the PRE Scale 1 is used to describe the intensity you would feel if you were chilling on the couch reading a book , magazine or the newspaper. So you are really in a relaxed, totally resting state.
The other end of the spectrum is level 10, this is where you are exercising so hard it feels like your lungs are going to burst, you feel faint or have the sickly feeling of an oncoming vomit.

The other numbers are a sliding scale in between these two extremes. Over time and with practice you can determine at what level you are working at by assigning a number that you feel is appropriate to how hard you are exercising.

For example if you were walking from the train station to the office then that could be at level 2 maybe 3. Suppose you came to a set of stairs and kept the same pace as your walk then you might hit a level 5 on your PRE Scale, but take the escalator and you would be level 1.5!!!
The benefit of this method in monitoring intensity is it works great on the days you feel energised because you will increase your output according to how you feel, but it works equally well on the days you feel rundown because it means you will take it a little bit easy to ensure you don’t over do it. So it is a win/win situation, you work harder when you feel you can and take it easy when you feel you need to.

Initially you will need to actively monitor intensity in this fashion, but soon you will learn to do it without thinking. Just take the time to assess yourself on a regular basis during a session so you keep you level of exercise at an appropriate level.

Good luck, keep training!!!!

JK