Shoulder Workout Builder
Interactive ToolShoulder Anatomy: Three Heads + Rotator Cuff
The deltoid has three distinct heads, each crossing the shoulder at a different angle. Most training programs over-develop the anterior head (front) through pressing movements, leading to rounded shoulders, poor posture, and impingement risk.
Anterior Deltoid (Front)
Flexes and internally rotates the shoulder. Already heavily worked in all pressing movements. Often overdeveloped in gym-goers.
Lateral Deltoid (Side)
Abducts the arm (raises it out to the side). Key for shoulder width. Best hit by lateral raises — with strict form, not momentum.
Posterior Deltoid (Rear)
Extends and externally rotates the shoulder. Usually the most underdeveloped head. Critical for posture and shoulder health. Needs dedicated work.
Exercise Guide: 7 Key Dumbbell Shoulder Exercises
Overhead Press
Anterior + LateralStart at ear height. Press directly overhead. Don't lean back — keep core braced and ribs down. Lower with control to starting position.
Mistake: Pressing in front of the body (bar path forward). Press straight up — ears between arms at the top.
Lateral Raise
Lateral DeltoidSlight forward lean and slight elbow bend. Raise to shoulder height with pinky slightly higher than thumb (external rotation). Lower slowly — 3 seconds down.
Mistake: Shrugging the traps to assist. If you need to shrug, the weight is too heavy. Go lighter.
Reverse Fly
Posterior DeltoidHinge to 45-60 degrees. Arms hang below chest. Raise arms out to sides keeping slight elbow bend. Squeeze shoulder blades together at the top.
Mistake: Using momentum and swinging. This isolates a small muscle — use light weight with full control.
Arnold Press
All 3 HeadsStart with palms facing you at chin height. Rotate out as you press up — end with palms forward overhead. Reverse on the way down.
Mistake: Rushing the rotation. The rotation is what makes this exercise unique — control it through the full range.
Face Pull (Dumbbell)
Posterior + Rotator CuffLying face-down on incline bench or standing with cables. Pull toward face, elbows high, thumbs pointing behind you. Externally rotate at the top.
Mistake: Pulling low (toward chest instead of face). The high elbow position is what targets the rear delt and cuff.
References
- Coburn JW, Malek MH. NSCA's Essentials of Personal Training, 2nd ed. Human Kinetics, 2012.
- Escamilla RF, et al. "Shoulder muscle activity and function in common shoulder rehabilitation exercises." Sports Med. 2009.
- Reinold MM, et al. "Electromyographic analysis of the rotator cuff and deltoid." AJSM. 2004.