Most trainers typically do 3-4 sets of an exercise, but with chins Arnold commonly used a technique in which he aimed for a total number of reps—say, 50—rather than target a particular number of sets: "On the first set you may do 10 reps. Perhaps you struggle with 8 reps on the second set. You have 18 reps now. If you make 5 on the third set, you have 23 reps. You continue to add them until you've reached 50, even though it may take you 20 sets to do it. That's how I built up my chinning power, and I was very successful with it."
Weight training and bodybuilding nutrition are sciences like anything else. There's biology and biochemistry and physiology, with rules and a base of evidence. Selling supplements, most of which are not needed, has become such a huge business in the commercial weight training and bodybuilding industry that it is almost impossible to know if you are getting an objective evaluation of a bodybuilding diet.

Stretching after each lifting session is extremely important in preventing injury. Flexibility allows your body to become much more able to handle the odd assortment of stresses that are placed upon it each day. I'm sure that the more hardcore of us bodybuilding fans heard that Branch Warren recently slipped and fell, landing on his outstretched hand and tearing his triceps in the process.

Heat grill. Combine lemon juice, chili sauce, Dijon mustard, basil and parsley in a baking dish; mix well. Place chicken in a baking dish. Cover dish and marinate chicken in refrigerator for 5 minutes. Drain marinade. Grill chicken over medium heat for about 10 minutes. Bake sweet potato in a microwave for 8 to 10 minutes. Serve chicken with baked sweet potato topped with pecans, broccoli and side salad.

Order of exercises: Design your plan so that large muscle groups are worked before smaller groups. The theory is that if you fatigue a smaller muscle group first, then the larger group won't work as hard as it can. For example, do bent-over-rows before biceps curls. Biceps work in both exercises, but since the larger and stronger back muscles are used in the rows, they wouldn't get a maximal workout if the biceps are fatigued. Another way to say it is that the biceps become the weakest link in the chain if you work them first.
To know how far 12 weeks of hardcore training have taken you, you’ll need to know where you began. In “Week 0” - a single workout to be performed one full week before taking on the rest of the program - devote an entire gym session to finding your three-rep max on five multijoint lifts. Your performance will provide you with a fair assessment of your strength so you can accurately measure your gains at the end of the program (Week 13).
Arnold frequently supersetted biceps and triceps movements—or, in other words, performed exercises back to back—to bring an enormous amount of blood into his arms. Blood carries oxygen and nutrients critical for growth, but these supersets also enabled Arnold to achieve his ultimate training goal: a killer pump. Supersetting a smaller muscle group like arms is easier than a larger one like legs, though Arnold often did that pre-contest as well.
JDB, great tip on cardio before weights. Having trained in a boxing gym for years, this is exactly how I would start each training session, even if I was going to focus on weights that day. Use to start off, 3-4 rounds on jump rope in the ring, alternating between fast high knees and then slowing it down. It was all continuous for about 10-12 minutes. Would then continue w basic calisthenics (mountain climbers, bw squats, burpees, etc.) for another 3-4 rounds. This was all done w boxing timer running in background. Would finish “warm-up” w some kind of pull-up/chin-up, dips, and hanging abdominal work. Then it was time for weights. This just overall improved my general conditioning/movement and never felt that my strength diminished when doing this. Actually, felt stronger due to increased blood flow.