First, you find the column that says 3 reps. Finally, follow that line left to find your RPE. In this instance, you can see that you need to train with 3 reps at a 9 RPE. A word of caution — some will want to in turn estimate their 1 rep max using this chart. A Word on Volume While intensity dictates a large portion of the training effect, the other side of the coin is how to auto-regulate your training volume in order to produce optimal training results. But first, I would like to discuss why auto-regulation is important when it comes to training volume.