It all depends for me.personanly I like to to do about 3-5 sets per exercise.And Ill due anywhere between 4-5 different exercise per bodypart.Some people say only do 3 exercises or so but I like doing more.Sometimes Ill even hit up like 6-7 different exercise per bodypart and do 2-3 set per.Pretty much I just like to mix shit up almost every workout or so maybe not totally but different order throw in a new exercise here and there tha I havnt used in a while or just use a different type of motion.keeps the muscles guessing and keeps me from getting bored with the same routine
It depends on the intensity of your sets. If you are tired one day, you might want to do 12 sets instead of 10 and use less weight. Id say around 10 for major groups like quads and lats ect.. And 6-8 for smaller like Bi's and Forearms ect..
It all depends on what your fitness level is and what muscle group you are working. For the most part though, you don't want to do anymore than 15 total sets for larger muscle groups and no more than 9-12 for smaller ones. If you are doing your sets and reps strictly using proper form and technique while taking your muscles to failure, you shouldn't need anymore than this.
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