perception of effort

[210toosmall]

ive noticed with coffe or energy drinks, it increases my perception of effort or makes it (the activity) seem harder or take more out of me.
now my questin is when training, does perception of effort matter?
meaning, if it seems harder are you doing more?

 

[BiggT]

No....you're only doing more when you are quantifably doing more. More weight over a set rep/range, more sets and or reps with a weight, or less rest between sets and exercises with the same weight/sets/reps/