Shoulders shrug to complete the upward fly
Upper traps assist the upward arc; upper pec underactivates.
Overactive muscles
Upper trapeziusLevator scapulae
Corrective work
Foam RollUpper traps↗StretchLevator scapulae stretch↗Upper traps assist the upward arc; upper pec underactivates.
Movement plane changes; shoulder impingement risk increases.