Health Jargon: What Does 'Workout Fatigue' Mean?
An aside: Is 'failure' considered 'success' when working out?
"Often fitness professionals state that when it comes to workouts “failure is success”, which means that you should workout till you cannot do anymore, and the following day it should seem as if a truck ran over you the last night. Even though it sounds like a hardcore and effective way to train, the fact remains that being too sore always and feeling too tired after every workout will soon fry out your central nervous system, and leave you overtrained. When this happens you will make progress very slowly, have mood swings and in general feel terrible,” states Sarkar.
Trainers generally advise one or two workouts to failure after ample rest periods or time gaps as a method to guage fitness progress. However, the average exerciser must not get carried away and workout till failure without proper supervision and guidance.