I have been working out with weights for nearly 30 years.  But there were a number of exercises I could not do well due to shoulder, tennis elbow irritations, and kinks in the knee.  I couldn't do shoulder presses, any type of dumbbell presses or flies, tricep pullovers, preacher curls, bench press, rear deltoid flies, barbell squats, etc. Upon switching to the resistance bands I have been able to do all of these exercises and more with no problems whatsoever.  And I have been doing very heavy resistance with the bands.  After having a bad shoulder for over 20 years, I never dreamed this kind of intense workouts would be possible again. the resistance bands have strengthened my shoulder.  I am stronger now than I have been in a long, long time.