Deltoid Deltoid • This muscle has a triangular shape like the Greek letter delta • Superficial and easy to palpate and found at the anterior, lateral, and posterior shoulder • Anterior deltoid lies next to the clavicular head of pectoralis major • Posterior to the deltoid are the infraspinatus, teres minor, teres major, and triceps brachii • The deltoid has three parts: – Anterior – Middle – Posterior Origin: Anterior Deltoid: Lateral 1/3 of clavicle Middle Deltoid: Acromion Process of Scapula Posterior Deltoid: Spine of Scapula Insertion: Deltoid tuberosity of humerus (middle lateral shaft of humerus) Deltoid Actions • Anterior Deltoid: – Shoulder Flexion – Shoulder Medial Rotation – Shoulder Horizontal Adduction (weak, synergist to pectoralis major) – Stabilizes the shoulder during abduction • Middle Deltoid: – Shoulder Abduction • Posterior Deltoid: – Shoulder Extension – Shoulder Lateral Rotation – Shoulder Horizontal Abduction (strong) – Stabilizes the shoulder during abduction Integrated Functions of Deltoid • All: – Assists in dynamic stabilization of the glenohumeral joint during functional movements • Anterior Deltoid: – Assists in eccentric deceleration of shoulder extension and lateral rotation • Middle Deltoid: – Assists in eccentric deceleration of shoulder adduction • Posterior Deltoid: – Assists in eccentric deceleration of shoulder flexion, medial rotation, and horizontal adduction Standing Overhead DB Shoulder Press Preparation : • Begin with good posture, shoulder blades retracted and depressed. • Maintain good posture throughout movement, with stability through the abdominal complex and neutral spine Instructions for Exercise Movement : • Position feet shoulder width apart, pointing straight ahead. • Start with the dumbbells at shoulder height, palms facing forward. • While maintaining total body alignment, push the dumbbells overhead. Other progressions: dumbbell, cables, tubing, stable to unstable surfaces Safety Considerations • AVOID letting your back arch at ANYTIME (this may indicate tightness in the lats and a stretching program should precede loading of this exercise). • Watch the hips (to ensure frontal plane stability) • Watch the scapula to see if there is excessive protraction. (‘winging’) – this may indicate an unstable GH joint Safety Considerations • Avoid laterally rotating the shoulders in the frontal plane, it stresses the shoulder capsule and glenohumeral ligaments which can cause anterior shoulder instability (your hands should be seen during the exercise) • Avoid presses behind the head • Seated DB presses on a bench should be avoided because of the stress on the shoulders and lower back Bilateral Shoulder Press Using Cables Preparation : • Maintain a tall body line throughout this exercise, good stability through the abdominal complex and neutral spine angles • Initiate a thorough dynamic warm up prior to starting this exercise -this engages the nervous system Bilateral Shoulder Press Using Cables • Movement : • Adjust the cable arms to a "low" position (as shown) • The exercise is performed using a split stance with a slight bend in the knee and only the back toe on the ground (REMEMBER – at some point you must switch lead legs in order to fully train the core) Bilateral Shoulder Press Using Cables • With the visual gaze straight ahead, perform a shoulder press • The hands will move from a wide position at the shoulders – to a close position overhead • Ensure that the elbows are directly under the arms throughout the movement • Return to start position and repeat • Watch for: – Inability to balance in staggered leg stance, excessive head forward, and protracted shoulders – these are indications that the exercise is too advanced and/or that the weight is too heavy. Prone on SB Posterior Deltoid DB Row Preparation : Place dumbbells in front of stability ball • Slowly roll onto the ball and position your body in optimal alignment (legs straight, head over shoulders and shoulders in line with hips). Prone on SB Posterior Deltoid DB Row Movement : From the start position, draw your belly button inward toward your spine. • While maintaining whole body alignment, lift the dumbbells by retracting and depressing the scapula • Slowly return dumbbells concentrating on SLOW deceleration and optimal balance. • Do not hyperextend the cervical spine. • Keep chin tucked and head parallel to floor. • Keep toes under heels. Prone on SB DB Shoulder Press Preparation : Maintain proper alignment through the kinetic chain by positioning the feet straight, glutes tight, ‘neutral’ spine angles, scapula retracted and depressed, and chin tucked for good cervical alignment. • Activate the core with a proper drawing in Prone on SB DB Shoulder Press Movement : • Choose light DB’s • Lie prone with your lower abs / hips on the stability ball, feet against the floor or wall • With the DB’s by your shoulders, perform an overhead DB press in line with the body. • Watch that the DB’s don’t ‘fall’ towards the ground as they extend over their heads. • Keep the core and glutes tight to avoid lower back discomfort Posterior Deltoid Stretch on SB • A great way to increase flexibility in the posterior shoulder capsule. Preparation : • Kneel on the floor with one arm on the floor. • Bend at hips, torso should be parallel to the floor. • Reach the opposite hand (palm up) across the body along the floor. • Movement : Slide one arm under the other arm as you rotate the spine. • Keep the hips stacked over the knees. • Muscles Stretched – Deltoid, Spinal Rotators, Lats, Upper Back Posterior Deltoid Stretch Kneeling on Floor Preparation : • Kneel on the floor with one arm on the floor. • Bend at hips, torso should be parallel to the floor. • Reach the opposite hand (palm up) across the body along the floor. Movement : • Slide one arm under the other arm as you rotate the spine. • Keep the hips stacked over the knees. • Muscles Stretched – Deltoid, Spinal Rotators, Lats, Upper Back