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."
The use of cardio exercise to get into shape was surprisingly nearly non-existent in the time period from the 1960’s to the 1980’s. As mentioned before, gyms were well equipped with barbells, dumbbells and heavy, basic machines. Cardiovascular equipment such as treadmills, stair masters and elliptical machines were not developed yet. Some gyms would have a couple stationary bikes included in the establishment but they were not nearly as comfortable or as advanced as the equipment that frequents health clubs today.
Start small and work your way up the ladder one step at a time. If you make too big of goals, you may never reach them, and you may lose motivation and interest, which will ultimately lead to giving up. However, if your goals are attainable, once you do reach them, a never before felt euphoria will rush through your entire body, and you'll finally realize why everybody who is in this is in it. This'll only push you even harder the next time, and the next time, and then the next time, and before you know it you look back at old photos and can't even recognize yourself.
One of the reasons why I love this specific routine so much is that is it easy for beginners. It does not have you doing a thousand reps and burning you out! Instead, you might notice the reps being a little lower than what you are probably used to and that is because the goal is to gain muscle-not worrying about endurance much. Also, you train 4 days per week-that screams “DO-ABLE” to me! You have two designated days where you work your upper body and the same goes for lower body.

Whey protein has been proven extremely effective when consumed before and after your workouts by people everywhere. After a year or so, you can look into creatine products. Supplements do not replace real food, so eat as much as you can and you can "supplement" your diet with some protein shakes and a multi. Eat as much lean meat as you can and consume some quality carbohydrates in your diet as well.
Attract sponsors to go pro. The more competitions you win and the more your physique starts to speak for itself, you'll need to start attracting sponsors, essentially going pro. This means that you'll be able to make money to train full time, without having to worry (at least as much) about doing other things to fund your bodybuilding. This is the dream that every bodybuilder works toward, and it'll only be available to a select few, with the genetics and the effort to make their bodies into Olympia-level physiques. Keep working toward this.
Is your resting heart rate jacked up today? Are you too sore from your last workout to walk? Did you only sleep a few hours the last night? Skipped breakfast and lunch? Congrats, you just earned yourself a rest day. In other words - go home. You aren't going to get anything but an increased risk of injury by training in any one of these conditions.

Most of your workout plan should include exercises that will stretch a minimum of two muscle groups in your body. For instance, the shoulder press will stretch your triceps and shoulders. On the other hand, squat will build your hamstrings and quads. Another important workout is bench press as it will work your chest, triceps, biceps and shoulders.

Lastly we come to full-body workouts. The 5 x 5 program could also be considered a full-body workout program to a degree, since you work almost all the major muscle groups with the three exercises you choose. But, true full-body programs will provide one direct exercise for each muscle group - quads, hamstrings, chest, back and shoulders (arms are worked when doing chest and back).
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.
Muscles don’t grow unless they need to overcome a resistance, and, to a point, the harder you need to contract them, the greater the “mechanical tension” and resulting growth stimulus will be. It’s the ‘use it or lose it’ principle. The most effective way to do that? Grab a weight (or resistance band) and have at it. Research suggests that mechanical tension disturbs the integrity of a muscle, triggering a series of changes that ultimately results in increases in not only size, but also contractile strength and power. In general, the heavier weight you can lift with good form, the more tension you produce, and the more you’ll grow.
Without any goals why would you even bother going to the gym? You need something to motivate you, something to aim for, otherwise you may spend a lot of time and effort in the gym for nothing. Having goals can determine what kind of routine you choose, what type of diet you follow, and ultimately is a great way to keep yourself focused. Many common goals include fat loss, weight loss, increase of size, increase of strength, etc.
You can reduce frequency. This would definitely be my first choice. If you’re using the 4 day upper/lower split, just switch to the 3 day version. The slightly lowered frequency/extra day of rest between each workout should GREATLY improve any recovery related issues you may have. If you’re already using the 3 day version and it still seems like it’s too much for you, see below.
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.