Shoulders shrug during the raise
Upper traps elevate; medial delt is underloaded.
Overactive muscles
Upper trapeziusLevator scapulae
Corrective work
Foam RollUpper traps↗StretchLevator scapulae stretch↗Upper traps elevate; medial delt is underloaded.
Upper trap takes over above the shoulder plane; impingement risk increases.