Once my body gets use to training and im past that "painful" stage that we all get when were outta shape, I give each body part at least 2 days rest before hitting them again, this goes for the secondary muscles as well (2 days rest). This took me many years of trial and error for me to find this perfect workout split, it will look like this below:


Monday - Quads/Calves
Tuesday - Chest/Forearms
Wednesday - Back/Bi's
Thursday - OFF
Friday - Hams/Calves/Forearms
Saturday - Shoulders/Tri's
Sunday - OFF

--REPEAT--

Everyone should try this, you will love the results as every time you train a muscle group, you will be able to hit it very hard as your muscles and secondary muscles will be nice and fresh and well rested