Some people want to know the best day to do Delts… It is really up to you but you should think like I do, because I like working my Delts on my Back Day at the gym. It is the back of the Shoulder and it doesn’t put extra stress on my Shoulder workout. Fatigued muscles can cause you to hurt you during your workout!
Muscle fatigue is the decline in ability of a muscle to generate force. It can be a result of vigorous exercise but abnormal fatigue may be caused by barriers to or interference with the different stages of muscle contraction.