To properly stress the body, you have to know how it works right? I’m going to cover basic anatomy for training. This will be like a crash course on how movement and muscles work and why working them certain ways or with certain exercises yields results.

Why do you need this?

So in the future, if you want to change something in your plan to get a specific result or activate a particular set of muscles, you’ll know how and why.

Key terms:

• Origin-where a muscle is rooted ,essentially, where the load is being pulled to.
• Insertion– Where the muscle attaches to pull in.
• Inferior- bottom or lower point
• Posterior– Back
• Anterior- Front

Example- the biceps originates in the shoulder and insert in the radius, allowing them to pull your arm towards you or flex.

Time to jump in!

Basic anatomy for training

Muscle groups

Pushing muscles of the upper body

Chest– Whenever you push something, reach out in front of you or manipulate anything to your front your using your chest. This main group consists of the Pectoralis major (your chest muscle), and the anterior Deltoid (front part of the shoulder). When you perform a bench press, these are the prime movers of the weight, and the primary muscles damaged. An accessory muscle for the chest and shoulder groups are the triceps, located on the back of your arms.

Shoulders– Or the Deltoids. The Deltoids are split into the anterior (frontal) originating at the collerbone, middle (lateral) originating in the middle of the shoulder, and posterior (back side) originating on the spine of scapula. They all insert into the side of the humerus. The anterior was mentioned above and helps with any movement in front of the shoulder. The middle delt presses upwards and lifts laterally from the sides, like a shoulder press or lateral raise. The posterior helps with retracting the arm, like rows. This is not to say they don’t all work at the same time, because they do. This is just a basic breakdown of their primary movements. There are numerous other deep muscles in the shoulder that serve to stabilize and assist in movement, but for the basics knowing how the delts work and how to target them is fine.

Triceps– Located on the back of the arm, the Triceps originate at the top of the humerus and inside of the shoulder blade and insert in the ulna and forearm. They assist in any pressing movement as well as anything involving extension of the arm. The Triceps and Biceps should be about equal in strength, a fact a lot of people overlook. Any exercise involving straightening the arm, like cable extensions or overhead tricep press, is primarily directed at these muscles.

Upper Body Pulling Muscles

Back- The back is made up of the Latissimus dorsi (A fan shaped m muscle originating in the spine, stretching from the pelvis to in between the shoulder blades and inserting in the humerus.). The Trapezius (originating from the spine right behind the head to the lower back and inserting into the shoulder blade). And the Rhomboids, which lie below the Trapezius, originating from the spine and inserting into the bottom and middle of the shoulder blade. These muscles all work in unison to retract the shoulder blade, like in rows, lift the shoulder (shrugs), depress the shoulder (straight arm lat pulldown). Individually, the lats (Latissimus dorsi) help pull the humerus downward and back (lat pulldowns, pullups). TheTrapezius, or traps, elevates the shoulder blade (shrugs) and helps with lateral movement of the arms. The Rhomboidsretract the scapulae towards the spine (rows) and help with elevation.

Biceps– The biceps or Biceps brachii, are the prime flexors of the arm. Any pulling movement involves the biceps at least partially. They originate in the shoulder and insert in the radius, as shown earlier. This allows them to pull the forearm towards the body (curls) and assist in anything requiring the arm to flex (lat pulldowns, rows).

Legs

The largest muscles in the body are in the legs. They work much like the muscles in the arms, flexors and extensors.

Quadriceps- The muscles on the front of your thighs, the quads, act as the triceps of the legs. This group is made up of 4 muscles, but they all work in a similar way. They originate in the top of the femur and front of the pelvis and insert into the front of the tibia. Any movement that involves extending the leg forward uses these as it’s primary movers. They are heavily involved in squats and running as well.

Hamstrings- Literally called the Biceps femoris, the hamstrings originate on the inferior posterior of the pelvis and insert into the posterior fibula and tibia. These muscles act with the Semimembranosus and Tendinosus as the biceps of the leg, flexing the foot up towards the glutes. They are heavily involved in deadlift, and assist greatly in squats. They also help bring the leg towards the body from a extended position.

Glutes– There are 3 muscles that make up the glutes, the Maximus, Medius and Minimus. The Maximus is what everyone is familiar with and all perform similar actions. They all originate from the lateral pelvis and insert into the superior portion or the femur. These are activated in deadlift heavily and any action that involves straightening the body or extending the leg backwards.

Calves- last but not least are the calf muscles or Gastrocnemius. These originate from the anterior inferior portion of the femur and insert into the achilles tendon, which attaches to the heel. The calf muscles work primarily to stabilize during the main lifts, but are used heavily in running and shock absorption as well as lifting the entire body onto the pads of the feet. These can be targeted by any machine or workout that involves pressing with the pads of the feet.

While I didn’t cover even close to all the muscles involved in exercise, but this is definitely enough to get a rough idea of how the major muscles work and how they’re activated. You can even create your own exercises as long as you know what muscles you want to activate and how.