Most people think that the only way to get big and strong was with the traditional fairly high-volume multiset method as used by Schwarzenegger. However, another popular theory is that if someone
wanted to get absolutely huge they must do only one set of each exercise to failure. Which is it?
The age-old question-one-set training vs. multiple-set workouts. I do have my own opinion on the subject, and there are scientific studies out there comparing the two types of training, but let's go back a bit and look at the proponents of these two styles, Arnold Schwarzenegger and Mike Mentzer.
Arnold will forever be known as one of the greatest bodybuilders of all time. Very few bodybuilders have been able to set a trend or dominate an era as he has. No one can ever accuse Arnold of not training intensely. In the movie Pumping Iron (which I recommend every bodybuilder see ... twice!) Arnold states that he will go all out no matter what. He has no fear of fainting from pushing himself to the limit. Another characteristic of Arnold's training was that he stayed in the gym for hours doing exercise after exercise, set after set, working tirelessly to forge his huge pecs and bis. I don't know if he was overtraining or not, but to be honest, any true bodybuilder would willingly submit himself to overtraining if the end result was a body like Arnold's. Many of the best bodybuilders in the world follow the high-volume approach programs, including Lee Haney, Ronnie Coleman and Lee Priest.
On the other hand Mentzer advocated training with only one exercise per bodypart (sometimes two) and only one set to absolute failure. For example, whereas Arnold or Lee Priest would do 14 to 16 sets until failure to totally blast biceps, Mentzer would recommend choosing one exercise per bodypart (say, the dumbbell curl for arms) and doing one set to failure. Then you hang up your gym shoes for the day, your biceps are done. I know some pros did follow Mentzer's teachings, but few bought into it completely. Both Dorian Yates and Lee Labrada felt that the high-volume approach led to overtraining. They performed less sets and reps than normal, for sure, but you'd never catch them doing just one set per bodypart. Perhaps they felt that Total Heavy-Duty Training (as Mentzer calls it) was ineffective when followed to the letter, but still had some good merit. Maybe they didn't totally trust Mentzer. After all, when he lost the Olympia in 1980 it was said that he ran to Arnold, crying and bitching in a psychotic manner. It wasn't unusual to come across Mentzer less than successful in Venice Beach over the greater part of the '80s. Only later did he clean up his act and adopt a more reasonable philosophical viewpoint. I still think he's wrong, but people continue to listen to him.
So what's my opinion? Well, I dug for some science on the subject and found that, even the eggheads who have compared one-set and multiple-set training agree that you can get equal results in terms of strength gains and muscle growth from either routine. (Look that up on medline if you don't believe me.) Even if Mentzer's ideals are crazy, I still think they have some merit. With one-set training at least you'll avoid overtraining. If you eat enough protein and calories, it's still a stretch to say that regular volume-training is going to slow your gains. Take one look at Ronnie Coleman. Is he overtrained?
I believe that one-set training is suitable for the advanced bodybuilder only. It's the same old story. You must teach yourself how to do a task before you get any better at it. Dorian Yates repeatedly said that you must teach the muscles over time how to get the most out of one set. If you aren't ready for it, chances are you'll miss the mark and wind up with some muscle fibers not getting stimulation. On the other hand, if you take a few sets to try to get the job done, you can be pretty sure you'll be hitting all the fibers for maximum muscle growth.
One of the brightest guys in the sport right now, Charles Poliquin will tell you that Mentzer's clients gain weight when they switch to his heavy-duty training style because with only one set you don't burn as many calories. If you don't burn as many calories in your training, you're going to gain weight - but how much of that weight will be fat? I believe in this little-known scientific training principle: You must train to the point where the muscle "depolarizes." This occurs when you subject it to a lot of contractions. When a muscle is repeatedly depolarized, meaning that it is subjected several times to an exercise taken to the point where it cannot contract any longer, then your muscle begins to release a number of growth factors, including IGF-1 and fibroblast growth factor. You won't get this release with one-set training.
To wrap it up, one-set training is okay for advanced bodybuilders only. Did Mentzer deserve to beat Arnold in 1980? No way! Nobody ever deserved to beat Arnold back then. I suggest you take what you think is rational about Mentzer's heavy-duty and apply it to your own needs, but don't necessarily follow his approach explicitly. There's not much science to prove it, and maybe he's too much of a loose cannon to totally entrust your training to.