love working out and living a healthy lifestle. I am always reading up on healthy foods, diets, and fitness.
Today I decided to research building your chest muscles and what exercises are best for the differnt parts of the chest. I found a post in a forum that was very informative and I think has alot of valuable information in it that anyone working on their chest would fine most useful. So I am posting it here for others to see and also so that I will be able to come back and refference from it easily.
EMG AND VARIATIONS OF THE BENCH PRESS
by Tom McCullough MEd., MSS
The bench press may be the most popular and widely used exercise used for developing the chest (Thompson, 1994). But go into any gym today and you will see quite a few different variations being done. There’s the decline, the incline, the flat bench and to make things even more complicated, all of these can be done with dumbbells. Is one better than the others? Which one should you use and what does each develop?
Well, this is where we must begin to separate popular ‘gym myths’ from reality. First let’s look at the claims of many bodybuilders. Most believe the angle of the bench has lots to do with what part of the chest you will use. So it is a pretty common belief among weightlifters that the decline bench targets the sternocostal head of the pectoralis major (the lower pecs) and the incline bench hits the clavicular head of the pectoralis major (the upper pecs). So obviously the flat bench must hit a little of both. What about the grip position? Should we use a wide grip or is a narrow grip? I’m sure most of us have heard that a wide grip uses more chest and shoulders and a narrow grip uses more triceps.
Is this common advice just another fine example of the ‘gym myth’ or is there actually some science to back these anecdotal claims? Before we attempt to answer this burning question let’s first take a look at what really happens when the bench press is performed. As most of us are aware the major muscle used in the movement of the bench press is the pectoralis major. While the pectoralis major is actually one muscle, it has two heads -- the clavicular head and the sternocostal head. The clavicular head or the upper pecs originate at the middle part of the clavicle. The sternocostal head or lower pecs originate at the costal cartlidges of the first six ribs and the adjoining portion of the sternum. Both heads span the chest and eventually join and insert on the humerus or the bone of the upper arm. It is pretty much accepted by sport scientists that the upper pecs are responsible for shoulder flexion or moving the arm upward and the lower pecs are responsible for shoulder extension or moving the arm downward (Lockhart 1974). So at this point it still seems logical to believe that the decline position may actually hit the lower pecs and the incline will hit the upper pecs.
But wait...before we draw any conclusions, let’s take a quick look at some of the other muscles involved in moving the bench press. First we have the triceps brachii. The major function of the triceps is to extend the elbow and shoulder joints. The triceps brachii actually consist of three heads (long, lateral, and medial). The medial and lateral heads attach to the upper arm and elbow performing extension of the elbow joint while the long head attaches to the scapula to extend the shoulder.
Next we have the deltoids. While the deltoid is only one muscle it actually attaches in three places giving it three distinct heads (anterior, lateral, and posterior). While the posterior and lateral heads are used as stabilizers in the bench press we are only going to be concerned with the anterior or front deltoids (McCaw, 1994). The front deltoids are responsible for flexion, by moving the arm upward and horizontal adduction, which is moving the arm toward the chest.
Now what does science have to say about the effectiveness of all of these variations in the bench press? As many of us are aware, when a muscle contracts it produces electrical energy. The higher the electrical energy the more work the actual muscle is producing. By attaching electrodes to the skin over the bellies of each of these muscles this electrical energy can be measured and read using an electromyograph (EMG). EMG studies can be then be performed on subjects to determine which muscles each of these variations in the bench press may effect. In a recent study Barnett et al (1995) examined the EMG activity of the upper pecs, the lower pecs, the triceps, the front deltoids and the lats using the decline, flat and incline bench press. This study will be quite useful in shedding some light on this confusing subject of pectoral development. So let’s get started!
The Sternocostal Head
One of the most common assumptions in the world of iron is that the decline bench is the best for developing the lower pecs. However, this familiar premise may be nothing more than another unfounded gym myth. According to the Barnett EMG study, the flat bench produced much more electrical energy in the lower pecs than did either the decline or incline positions. "I agree with this research" says NPC National Champion and pro bodybuilder Jay Cutler, "The flat bench is much better for lower pec development than the decline."
But what is the best grip to use? EMG studies have also shown that when doing the flat bench, the muscle fibers of the lower pecs are activated the most when using a wide grip. "This is very much true," adds Fred Hatfield, Ph.D. "A wide grip with the elbows out will cause much more lower pec activation." However, whether you choose to use a wide or narrow grip, we can assume that using the decline position to target the lower pecs is just not justified. Eddie Robinson, IFBB pro bodybuilder states, "I feel the flat bench press, with a wide grip is best for over all pec development, but you do not want to go so wide with the grip that you over stress the shoulders."
The Clavicular Head
Now we all know that the incline bench hits the upper pecs. Right? Since the upper pecs seem to help to raise the arm, this would make sense. The incline position would put the arm in more of a flexed position than either the flat or decline positions. According to EMG studies this advice seems to be pretty much true. The Barnett study tells us that the incline position produces just slightly more electrical energy in the upper pecs that either the flat or decline positions. However, the flat bench was found to be very close. While the difference between the two was considered insignificant, the slight advantage of the incline over the flat bench in upper pec activation may be just what some of us need to further develop the upper pecs. "This is all very true," says Robinson. "There is no doubt the incline bench hits the pecs more than the flat bench."
Cutler agrees and says, "I personally feel upper pec development is very important for a bodybuilder. So I concentrate more on the incline bench that I do the flat bench." While the incline position may provide slightly greater upper pec stimulation Hatfield contends, "The same thing can be accomplished by using the flat bench. I would suggest lowering the bar to the upper pecs instead of the lower pecs (as normal), using a wide grip with the elbows out."
Nevertheless, if you are going to use the incline position to target the upper pecs, a narrower grip has been shown to best activate them. Professional bodybuilder Mike Francois agrees and says "A grip that is just a little bit wider than shoulder’s width really hits my upper pecs best." But Sal Arria, D.C., founder of the International Sport Science Association and former powerlifting champion warns: "Using a wide grip can involve too much front deltoid and can cause the deltoids to slam against the acronium process, causing trauma to the muscle."
The Triceps Brachii
I’m sure most of us have been told that a narrow grip hits more triceps than the wide grip. The close grip bench is widely used by powerlifters to develop strength in the triceps to accomplish those massive bench press attempts. According to the EMG study this is very true. The narrow grip when done in a flat position, produced more electrical energy than the incline or decline positions. It should be noted though, that the decline position was pretty close. Cutler explains, "While the decline may be close, I prefer to target the triceps using the flat bench with a narrow grip." Professional bodybuilder Mike Francois agrees, "The flat bench with a narrow grip is a great mass builder." "A narrow grip means your hands should be at your body’s width," Dr. Arria warns, "If you want to create a permanent wrist injury, go with a extremely narrow grip."
The Anterior Deltoid
Since the front deltoids are used for flexion of the arm, it makes since that the incline bench would activate the deltoids much more than the flat or decline positions. Once again our EMG study agrees. The incline bench press with a wide grip produced more electrical energy than the narrow grip. Francois remarks, "I agree! The greater the incline of the bench the more the front delts will be activated." Dr. Arria adds: "While the narrow grip is a stronger position, the wider grip produces more stress to the muscle."
Don’t Forget the Dumbbells!
Does the use of dumbbells in chest training change any of the rules? Absolutely not! "The rules we have discussed absolutely do not change when dumbbells are used, but what the use of dumbbell in training does is enable the lifter to have a much greater range of movement," claims Dr. Arria. "Further growth can be stimulated from these deep ranges of movement." Cutler agrees and says, "I think you should expect the about the same results with the use of dumbbells except it is much easier to isolate the pecs."
In conclusion, most of could benefit greatly by just depending on the flat bench to gain mass in the upper and lower pecs. However, you must custom tailor your training to meet specific goals. If you have a particular body part that needs further development you must find an exercise or angle that will stress that particular area even more. Therefore variations in the angle of the bench and the grip are important to optimal development of muscles of the pecs, shoulders and triceps.