Shoulder shrugs during the raise
Upper trap elevates instead of medial delt lifting the arm.
Overactive muscles
Upper trapeziusLevator scapulae
Corrective work
Foam RollUpper traps↗StretchLevator scapulae stretch↗Upper trap elevates instead of medial delt lifting the arm.
Body tilts to assist the raise; QL and lateral trunk do the work.