Hip flexes to assist — thigh swings forward
Hip flexion replaces the isolated knee flexion; hamstring loses its load.
Overactive muscles
Hip flexorsRectus femoris
Corrective work
Foam RollHip flexors↗StretchHalf-kneeling hip flexor stretch↗Pull · Lower Body
Standing Leg Curl Machine
Coaching cues
- Stand facing the machine; pad just above the heel of the working leg
- Curl the heel toward the glute — knee flexion only; thigh stays vertical
- Pause at peak contraction; lower slowly under machine resistance
- Trains the hamstring unilaterally in a standing position
Common faults 2
Trunk leans away from the machine
Erectors assist as the hamstring fatigues; form breaks down.
Overactive muscles
Erector spinaeQuadratus lumborum
Corrective work
Foam RollErector spinae↗StretchQL side-bend stretch↗