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Barbell back squat

Barbell

Primary muscles

Secondary muscles

The back squat loads the knees and hips together. The quadriceps straighten the knee, the gluteus maximus and adductor magnus extend the hip out of the hole, and the spinal erectors keep the torso from folding forward.

Form cues

  • Brace before you descend
  • Knees track in line with the toes
  • Drive the floor away and stand up through the hips and knees together
Full barbell back squat guide →

What each muscle does in the barbell back squat

MuscleRoleAction
QuadricepsPrimaryExtends the knee; the rectus femoris also flexes the hip
Gluteus maximusPrimaryExtends and laterally rotates the hip
Hip adductorsSecondaryAdduct the hip; the adductor magnus also extends it
HamstringsSecondaryFlex the knee and extend the hip
Erector spinaeSecondaryExtends and laterally flexes the spine
SoleusSecondaryPlantarflexes the ankle

Primary muscles are the prime movers; secondary muscles assist or stabilise. The balance shifts with grip, stance, range of motion and technique.

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