Scapula doesn't fully retract before the hold
Partial retraction means the rhomboid never reaches peak contraction.
Overactive muscles
Biceps brachiiUpper trapezius
Corrective work
Foam RollUpper traps↗StretchLevator scapulae stretch↗Partial retraction means the rhomboid never reaches peak contraction.
Erectors assist the sustained hold position; mid-back loses the load.