Tyler Robbins Fitness

B.Sc. Biochemistry, Certified Strength and Conditioning Specialist (CSCS), Certified CrossFit Trainer (CCFT/CF-L3), USA Weightlifting Level 1

Filtering by Tag: Diamond Delts

Learn all about your deltoids

Source: http://en.wikipedia.org/wiki/Deltoid_muscle

Source: http://en.wikipedia.org/wiki/Deltoid_muscle

Similar to the triceps, there are 3 heads to the deltoids; the anterior or front (right, in red), the middle (right, in green), also known as the lateral, the outer, or side, and the posterior (right, in blue) or the rear.

  • The anterior deltoid originates on the anterior surface of the clavicle (collarbone)

  • The middle or lateral deltoid starts on the acromion and spine of the scapula/shoulder blade (seen below), 

  • The posterior deltoid starts on the spine of the scapula (seen below).

All 3 heads then come together and attach on the humerus (upper arm).

The deltoids are involved in nearly every single thing you do, including things like deadlifts. Although the shoulder does things like abduct the arm (humerus), rotate the humerus, aid in pressing and throwing, etc. the shoulder also has to work hard to keep the humerus from dislocating from the humeral socket. The shoulder is unique in that it allows for the greatest range of motion out of all joints in the body, however, this can also increase the risk of injury.

Source: http://en.wikipedia.org/wiki/Deltoid_muscle

Source: http://en.wikipedia.org/wiki/Deltoid_muscle

Source: http://en.wikipedia.org/wiki/Deltoid_muscle

Every workout that involves the shoulders should begin with a thorough warmup to get the soft tissues that make up the stabilization and strength of the shoulder warm, as well as activating the muscles to ensure stability. Even on days when you are not directly working the shoulders, it is beneficial to do a routine like the following to increase the strength and durability of the entire shoulder girdle.

Take deadlifts, for example. Although you are not abducting your arms or pressing weight overhead, your deltoids need to work hard to engage the head of the humerus and prevent it from literally being pulled from its socket.


Anterior Deltoid

  • Primarily used to abduct the shoulder when the arm is externally rotated
  • Flexes the arm at the shoulder
  • Internally rotates the arm

Lateral Deltoid

  • Primarily used to abduct shoulder when the arm is internally rotated

Posterior Deltoid

  • Primarily used to the extend the arm at the shoulder

Abduct when arm is externally rotated

Flex arm at shoulder

Internal rotation

Abduct when arm is internally rotated

Shoulder extension

"The Armoury" - 30 minute Shoulders & Arms Workout


"The Armoury" Worksheet


I'd be interested in your rational for structuring the workout the way you do: for example, the shoulders sequence seems to be compound work then iso work and the burnout is strip down sets. Why not, for example, do iso work then compound work in a multi-set? I'm not saying there is anything wrong with how you structured the workout; I am just wondering why you put it together that way.

I always prefer large muscle group, multi-joint actions over isolation work. So, for example in this workout, shoulders take priority over the biceps or triceps. Since the triceps are so heavily involved in shoulder pressing, if I have an isolation set of triceps prior to shoulder presses, then I wouldn't be able to maximize my benefits from the shoulder presses.

Incorporating the band into the warmup was also a good idea.

Thanks! Not sure why they don't use bands. I have had a couple funny little tweaky things happen to my shoulders in the past, so I definitely know that some pre-hab work is good for me to keep things working smoothly.