Leg Extension

Leg Extension

The leg extension isolates the quadriceps in a pure machine isolation movement.

Muscles Involved

• Quadriceps (4 heads) : pure isolation

Step-by-Step Instructions

Step 1 — Position

Seated, pad against lower shins.

Step 2 — Extension

Extend legs contracting the quadriceps.

Step 3 — Contraction

Hold 1-2 seconds at top.

Step 4 — Return

Lower controlled.

Sets and Reps

3 sets of 12-15 reps. Moderate loads.

Common Mistakes

• Loads too heavy : knee shear with excessive loads
• Momentum : strict and controlled movement
• Aggressive lockout : do not force final extension

Safety Tips

Moderate loads mandatory. Risk of cruciate ligament shear with heavy loads. Excellent as pre-fatigue before squats.

Variations

• Unilateral : one leg at a time
• Slow tempo : 4 seconds up, 4 down

Who Is This Exercise For?

All levels with moderate loads. Complementary exercise, not a squat replacement.