Who Will Have the Biggest Biceps?

[quote]Pantherhare wrote:

[quote]LoRez wrote:
As an example, let’s say you could theoretically completely isolate the clavicular head of the pecs.[/quote]

I get what you’re saying, but in your example, the different portions of the pecs are still hit with isolation exercises like flyes. See Contreras’ experiments with EMG.

Well, I did say theoretically. I know you can’t actually completely isolate them.

In the context of arm training, you can actually do a fairly decent job of isolating the particular muscles and respective muscle heads, but without also developing the pecs, lats, deltoids and forearms (whether by design, or by accident), that the body will limit the amount of growth in the biceps, triceps and brachialis, so as to retain some amount of balance across the shoulder and elbow joints. Not definitive, just my understanding.

Sure, I mean, lets say you actually isolated all 300 or so muscles of the human body in your bodypart split, ok, I’ll agree.

Mild sarcasm aside, my point was more that things like underdeveloped subscapularis and serratus anterior could actually hold back pec development, if they were neglected in a training split. The working hypothesis being that while the body will allow you to get things quite imbalanced, it still puts on its stops if you go too far.

In contrast, by using certain compound movements, (and in this case, some sort of high incline or overhead press), some of those smaller structural muscles will be trained “by accident” and the body will consider it safe enough to overdevelop the showier muscles.

Again, though, all of this is speculation.

But my take is that all things equal, if one person were to just train their biceps, triceps and brachialis (in an intelligent manner, with sufficient food), and completely ignore everything else, and someone else were to train those three muscle groups, and also their lats, delts, and pecs, that the 2nd person would have larger arms.