Major Muscle Groups

The anatomy of bodybuilding includes knowing what muscles are located where and how they are grown most effectively. It can be confusing, so as you read this article, find a mirror and locate the muscles on your own body. Knowing the anatomy of your body can be very helpful. When trying to sculpt your body, you really need to know a little about your anatomy.
It is very important for those of us who are regular muscle building enthusiasts to pay special attention to the muscle group’s structure as well as function while training. Though it is possible to get good results from simply performing exercises, it would nevertheless be of greater benefit to you to first understand the basics of bodybuilding anatomy and then proceed to build up an impressive physique. If you use your knowledge about your muscle group’s structure as well as function to properly train, you will obtain the maximum from your endeavors and thus maximize the body’s strength as well as get larger and more powerful muscles. In addition, if you know your bodybuilding anatomy well such as understanding your muscle anatomy you will know clearly what the muscle appears as, and thus realize how the muscle’s work while you are bodybuilding.
Knowing the major muscle groups and the weight lifting exercises that work each of these basic muscle groups is very important to improving your body.
Athletes, trainers, bodybuilders and even regular gym-goers need to understand exactly how the muscles in their body function, so that they can work them properly to make them stronger and bigger.
The muscles of your body which you can work out can broadly be divided into four categories – upper body, arms, legs, and buttocks.
Names of Muscles
The name of a muscle typically tells us something about its structure, location, size or function. Shape is described in such muscles as the trapezius, deltoid or gracilis. The corresponding shapes are trapezoidal, triangular and slender, respectively. Gluteus maximus and gluteus minimus, the muscles that make up the buttocks region, are two names that indicate relative sizes.
Some muscles are named according to their number of “heads.” The head is defined as the expanded, rounded surface, or belly, of a muscle. The biceps muscle has two heads, hence the prefix bi. The triceps has three heads, and the front thigh muscle, called the quadriceps, has four heads.
Muscles can also be named according to the direction of their fibers – transverse (across) and obliques (slanted). They indicate the direction of the muscle fibers with respect to the structures to which they are attached.
Such terms as supraspinatus and infraspinatus indicate relative position – supra indicating above the spine of the scapula, and infra below the spine of the scapula. Familiar to most bodybuilders are the latissimus dorsi. They are named as such to indicate that they are found laterally on the body toward the dorsal, or back region. (Just remember where a shark’s dorsal fin is located.) Likewise the rectus abdominis is a straight muscle located in the abdominal region.
Now each of these muscles have separate isolation exercises to target that particular muscle and compound exercises which targets more than one muscle group and joint.
The human skeleton is covered by approximately 650 muscles, which create the distinct contours and shape of the human body. It should be noted that there are many more muscles in the body that are not addressed by this muscle anatomy diagram, however the muscles that are of primary interest from a fitness and exercise perspective are covered by this muscle anatomy diagram.

Upper Body
- Pectorals (“pecs”—chest muscles)
- Deltoids (“delts”—rounded muscles at the top of the shoulders)
- Latissimus dorsi muscles (“lats”— muscles extending from under the armpits across the back to the spine)
- Trapezius muscles (“traps”—muscles extending from the neck to the middle of the back)
- Spinal erectors (horizontal muscles extending down the back to just above the waist)
- Obliques (muscles on the side of the torso, next to the abdominals)
- Intercostals (diagonal muscles across the ribs, just above the abdominals)
- Serratus muscles (diagonal muscles slightly above the intercostals, near the pectorals)
- Abdominals (“abs”—vertical muscles extending the length of the abdomen)
Arms
- Biceps
- Triceps
- Forearm flexors (muscles of the inside of the forearm)
- Forearm extensors (muscles of the outside of the forearm)
Legs
- Quadriceps (“quads”—muscles at the front of the thigh)
- Hamstrings (muscles that extend from the back of the thigh to the lower leg)
- Gastrocnemius muscles (upper calf muscles)
- Soleus muscles (lower calf muscles)
Buttocks
- Gluteus maximus muscles (“glutes”— muscles of the buttocks)
