Auto-regulation within the strength & conditioning world is generally defined as adjusting volume (number of sets & reps) and/or intensity (weight/load used or lifted) based upon how you feel in a given day, during a given workout.
So, why is this important?
Most training programs are designed with the expectation that the exact amount of sets, reps and load that are written will be completed. The issues arises when a trainee has an “off-day” for whatever reason (sore, illness, familial issues, etc.). You see, you will not be in perfect condition for each workout - not even close. But don’t fret…
This is where you can utilize auto-regulation to benefit your progress and keep from over-doing it. If you’re struggling during a workout or know ahead of time something is “off,” you can adjust your reps from 3 down to 5, or your percentage from 75% to 65% - even shave off a set or 2, if needed.
Learn to listen to your body!