Fitness doubts: Are the chest muscles really divided into upper, middle, and lower?

I often hear others say that the training of pectoral muscles should be comprehensive! Take into account the upper, middle, lower, inner, and outer edges! This will make the pectoral muscles fuller and beautiful!

　　But is the chest really divided into upper, middle and lower?

　　In fact, from the anatomy, there are only two main groups of muscles in the chest, namely the pectoralis major and pectoralis minor, and there are no upper, middle and lower chest muscles.

　　Is it hard to believe? Let’s take a look!

What is muscle?

　　I will briefly introduce muscles first. Human muscles can be divided into three categories: myocardium, smooth muscle, and skeletal muscle. The muscles we are going to discuss are skeletal muscles, muscles that can be controlled by our will.

　　Look at the picture below, a group of muscles is made of bunches Small muscle strands are composed of thin muscle fibers. To give an analogy, a group of muscles is like wrapping many rubber bands with cloth.

　　We will magnify the muscle fibers with a microscope and we will see the following picture:

　　When relaxing, the red lines (actin microsilicon microsilicon microsilicon) intersect less, but when they tighten and the intersecting positions increase, the muscles contract:

　　This shows that there is only one direction for muscle movement, so this can explain why muscles are like wrapping many rubber bands with cloth.

(Note: Follow the fitness bar WeChat public platform, subscribe to the account to search "Fitness Bar Network" or "Click to scan and follow")

Related recommendations:

　　Chest muscle mid-slit exercise method - butterfly machine chest clamping

　　Dormitory fitness guide: Advanced tutorial on pectoral muscle training

How to train pectoral muscles big and thick? Come and try this set of training

2 pages in total: Previous page 12 Next page