The coveted bench press. The lift everyone asks about. The lift that is used to impress and show masculinity. It is over-rated, yet one of the most popular and important chest exercises there is. Many people, like me, start out performing this movement and found that it worked great for pectoral muscle growth but did
not and still do not know why. The reason for its ability to produce chest muscle growth better than most other chest exercises has to do with the amount of overload that is able to be put on the muscles.
Importance of Mechanical Overload
Bench press, being a large compound movement, enables you to put a great deal of tension on the muscle. This is probably the most important benefit of bench pressing as compared to other more isolated pectoral contraction movements. Mechanical overload is one very important mechanism for muscle growth.
By progressively overloading your pectoral muscles on the bench press can cause muscle growth in two ways: through satellite cell activation and through the increase in protein synthesis. For either of these to happen the intensity of the lift must be high in order for the muscle’s mechanoreceptors to overloaded, stimulating muscle growth.
Increased Protein Synthesis
The mechanical signals that go throughout your body when performing different lifts lead to a process called mechanotransduction. In this process the signals from mechanical movements are converted into biochemical processes. This process stimulates the mTOR (mammalian Target Of Rapamycin), which is a specialized protein and is important in muscle hypertrophy. Mechanical overload is just one of the many ways that the mTOR can be activated. For activation, the energy level and the stress of the muscle cells must be high, such as that from a heavy compound movement as bench press, for mTOR to be activated which in turn will help cells rejuvenate and rebuild by increasing protein synthesis.
So not only does there need to be muscle stress, but there also must be enough energy inside the cells for mTOR to be fully activated.
Satellite Cell Activation
Satellite cells are considered muscle stem cells and are capable of forming different muscle cell types, contributing to the muscle. They are activated in response to damage done in the body. In this case signals from the overloaded muscle will activate the satellite cells. These satellite cells are located outside of the muscle. When activated many fuse with myofibers of the muscle and form protein strands within the muscle, working to repair the damaged tissue. A smaller amount form new muscle nuclei (myonuclei). With more nuclei your muscles can synthesize additional amounts of protein. So the activation of satellite cells can lead to muscle hypertrophy in two ways.
So the More Tension the Better?
The muscular tension required in mechanical overload must be high to open up the anabolic pathways. However, going too heavy (too much tension) has been shown to be counter intuitive. This is why bodybuilders often see better muscle development from lifting in the higher rep range (generally 8-15) as compared to power lifters who lift more weight for fewer reps and generally have less muscle mass. The amount of bench tension on your muscles from bench pressing can stimulate growth arguably more than any other lift (I am talking about all forms of bench press: dumbbell, incline, etc. as they all are capable of being used to greatly overload the muscle).
Now you know a little more information on why bench press and other heavy compound movements are so beneficial when it comes to muscle growth. Remember next time it is chest day, if your chest development is lagging don’t forget to bench (as if anyone could forget).