[quote]BONEZ217 wrote:
Read an anatomy book please.
Pec sweep is genetic. [/quote]
Yep. You either contract the entire muscle fiber or contract none of it. The pecs have muscle fibers that run horizontally so you can’t target “inner” or “outer” chest.
[/quote]
Hmm, well the picture here is not anatomically correct according to my anatomy information source. All three heads should insert on the humerus (crest of greater tubercle). In this pic, most of the pec fibers appear to go nowhere. Maybe this guy can flap his ribs.
Also, there is apparently a form of “in-series” hypertrophy where sarcomeres are added to the length of the muscle (or conversely, are removed in adaptive shortening). People who have the joint mobility/ROM to move the origin and insertion further apart may be getting some of this lengthening hypertrophy along with the other forms. Many people I see in the gym have shortened pecs with reduced ROM (myself included, but I’m improving mine). In this case, even in a stretch-position movement like pec deck or flyes, the shoulder internally rotates and elevates as the humerus is abducted. You can FEEL a wicked stretch in your shortened pecs in this lousy movement pattern, but you are NOT moving the insertion physically away from the origin as much as should be anatomically possible.
[quote]BONEZ217 wrote:
Read an anatomy book please.
Pec sweep is genetic. [/quote]
Yep. You either contract the entire muscle fiber or contract none of it. The pecs have muscle fibers that run horizontally so you can’t target “inner” or “outer” chest.
[/quote]
I did post a “theory” about tilting dumbbells inwards and outwards to target origin and insertion points of the pectoralis major. Didn’t get much traffic in that thread however, a poster did come in saying that he had the same idea and even ran it by his teachers etc. (this was a long time ago just trying to remember).