The back is a complex part of the body. It contains many muscles, all of which play an important role in stability and maintaining good posture. The following guide will help you understand what these muscles are and how they function.
Major Back Muscles
The back muscles are important for supporting the body and maintaining posture. The major back muscles include the latissimus dorsi, erector spinae and trapezius. They're located on either side of the spine and around the shoulder blades or scapulae.
The latissimus dorsi attaches to your lower ribs and pelvis (pelvic girdle). It stretches diagonally across your upper back to attach onto each humerus bone in its respective arm socket joint at what's called an "intertubercular groove." Its function is primarily to adduct (bring together) both arms toward each other; however it also helps extend them away from each other as well as rotate them inwardly toward each other when necessary--such as during climbing activities like rock climbing or skiing downhill slopes!
The erector spinae attaches directly below where two vertebrae meet at their bottom surfaces near where they intersect with one another vertically by means of transverse processes located laterally along both sides just above where nerves exit out into space outside between two adjacent discs within spinal canal tissue surrounding these bones' intervertebral discs so that these nerves coming from brain stem/cervical region travel through spinal cord before exiting out into world outside body.
Latissimus Dorsi
The latissimus dorsi, or lats for short, is a large muscle located on the side of your body. It helps with arm movement and extends from your upper back to your lower back.
The lats are attached to many bones including:
- Spine - inferiorly
- Ribs - laterally
- Scapula - posteriorly
Trapezius
The trapezius is a large, flat muscle that covers most of the upper back and neck. The trapezius has three parts: the lower (or base), middle, and upper portions.
The lower portion runs from your spine to just above your shoulder blades. Its main function is to raise your shoulders and hold them in place while you move other parts of your body. It also helps you turn or twist your head from side to side or up and down when doing things like turning pages in a book or magazine or looking at something over one shoulder while standing up straight (rather than bending forward at the waist).
To identify this part of your trapezius muscle group look for two bumps right above where it connects with bone on either side of centerline between sides - these are called "mastoid processes" because they resemble masts on ships! This can be difficult unless someone points them out first though since they're buried under layers upon layers of fat/muscle tissue so don't worry if yours aren't as obvious as mine - just try searching around until you find two roundish bulges instead :)
Rhomboids
The rhomboids are two muscles that lie between the shoulder blades. They pull the shoulder blade down and back, which helps to stabilize the shoulder joint. The rhomboids also help rotate your upper arm inward (adduction).
The rhomboid major is larger than its counterpart, but both work together to produce abduction of your upper arm (moving it away from your body). These muscles are involved in lifting heavy loads or pushing something against resistance.
Levator Scapulae
The levator scapulae is located on the upper and outer side of your scapula, or shoulder blade. It helps raise your shoulder blade so that you can shrug or lift your arms above your head. The levator scapulae also works with other muscles to rotate (or move) your shoulder blades.
Erector Spinae
Erector Spinae is a group of muscles that run along the spine. This group of muscles helps to hold the spine erect and maintain posture, as well as rotate the spine. It's made up of three parts:
- Iliocostalis (inner section)
- Longissimus (middle section)
- Spinalis (outer layer).
Takeaway:
- The latissimus dorsi is a large muscle that extends from the lower back to the outer edge of each shoulder blade. It helps you lift your arms above your head and bend forward at the waist.
- The trapezius is a triangular-shaped muscle that covers three regions: upper, middle, and lower. It lifts the shoulders when you shrug them up toward your ears or pulls them down when you shrug them backward (such as when holding heavy objects).
- The rhomboids are two large muscles located between your shoulder blades that help raise and rotate your shoulders inward--for example, when reaching behind yourself to adjust something on a table or dresser drawer handle. They also hold up some of our internal organs such as our kidneys so they don't sag too low inside us!
- Levator scapulae runs along either side of spine from base where it attaches near neck all way down through shoulder blades where attachment point is located just below spine level just above where ribs meet it; this muscle helps keep shoulders level during activities like pushups where feet aren't touching ground yet still need support
Conclusion
The back is one of the most important muscle groups in the body, and it's also the most difficult to exercise. You can strengthen your back with simple movements like pushups and planks, but if you have a specific problem area like lower back pain or tight shoulders, it may take more targeted exercises to help relieve those issues.
