The deltoid and bicep muscle are delicate muscles surrounded by delicate joints. I can safely say that most, if not all professional bodybuilders are on some type of anabolic steroid. Any natural bodybuilder will be overtraining by the second exercise of these routines. Also, after 60 minutes or training, natural bodybuilders androgen levels plummet with the increase of cortisol, which is a catabolic (muscle wasting) agent. With this in mind, it is virtually impossible to have enough endurance to get through routines like this without killing your time and muscles.
For a natural bodybuilder, even on creatine and/or ZMA, which can increase muscle endurance and recovery and decrease the chance of overtraining, doing only four sets of an isolation movement is sufficient. Keep in mind this is after two to four exercises of a compound movement. Also remember that one set of four different exercises stimulates your muscles more than four sets of a single exercise. An example bicep workout is:
1x10 - Super 21's
1x10 - Cable Curls
1x10 - Alternate DB Curls
1x10 - Hammer Curls
Second, don't follow the training schedule practiced by professional bodybuilders. Though Arnold and Ronnie Coleman can train six days a week and still recover, teenagers can't. Only athletes on steroids can recover fast enough to work each muscle group to failure twice a week. Some pro's also need to train twice a day! Teenage bodybuilders should only need to work each body part once a week and maybe twice for lagging body parts.
A good schedule to train is:
Monday - Train
Tuesday - Train
Wednesday - Off
Thursday - Train
Friday - Train
Take the weekend off
Also, failure training has become a very popular training method. An issue of testosterone has reviewed this very well. Most coaches recommend their athletes to build up to failure for two weeks and go to failure on the third week. They also say that post-failure reps (forced, partial) are mostly counterproductive for natural athletes and should only be used on a limited basis and within a prioritized plan.
Lastly, you cannot change the shape of your muscles! Nasser El Sonbaty will never be able to build Mike Matarazzo's freakishly huge arms whether he is on steroids or not. Saying you can lengthen your biceps or expand your rib cage is not only physically impossible but saying it's possible for Lee Priest to lengthen his hamstrings so he can be as tall as Arnold! When it comes to "peaking" your biceps, it is a double-sided topic that Testosterone covered thoroughly. No, you cannot physically make your biceps higher but you can make them look higher. To elaborate, good development of the shorter head or bicep brachio-radius can make it seem like you have a higher peek. This is best shown in the back-double-bicep pose. Exercises that prioritize the brachio-radius and brachialis are Hammer Curls and Reverse Curls.
In conclusion, make sure that the routines, ideas and methods you read about applies to you before you practice it. Though Muscular Development has a lot of researched articles in it, see whom they researched. Results from research done on adult athletes using steroids will be different from research done on obese women or old, impotent men. Make sure those article's pertain to you before you try what they say. FLEX rarely has researched articles. The bodybuilder writing the article has only tested the routine he is doing on himself. Does your body respond to things the same way Kevin Levrone's body does? This means you can safely throw away the promises like "If you follow my 8-week bicep shocker, you can also put on three inches to your arm measurement!" For legitimate research, look to Testosterone and Muscular Development. To be sure an article is researched, look at the end of it for references and go to that reference to see if the research pertains to you.
I hope this article helps you train smarter for your quest for mass or cuts. Good luck!
"Pikes Peaks Biceps" Testosterone November 2001: 56
"Training To failure" Testosterone November 2001: 73
Holman, Steve "No Wimps" IRONMAN May 2002: 209, 212