Trunk leans to assist the curl
Body rocks to generate momentum; bicep loses isolation.
Overactive muscles
Erector spinaeQuadratus lumborum
Corrective work
Foam RollErector spinae↗StretchQL side-bend stretch↗Pull · Upper Body
Concentration Curl
Coaching cues
- Seated; elbow braced against inner thigh
- Full supination at top — rotate pinky up
- Lower to full extension — don't cut the range
- No trunk lean or hip drive
Common faults 2
Elbow lifts off the thigh
Loss of bracing point; upper arm swings forward.
Overactive muscles
Anterior deltoid
Corrective work
StretchDoorway pec stretch↗