Leg extension unilateral machine

Purpose of the exercise

Isolation exercise for the quadriceps with a focus on identifying and correcting asymmetry. Improves single-leg quad strength, develops neuromuscular control per leg and helps restore strength after unilateral injuries. Also effective for preventing a stronger leg from compensating the weaker leg.

Supplies

• Leg extension machine
• No further material required

Starting position

1. Sit in the leg extension machine
2. Set the machine as for bilateral version
3. Place only one single under the pad/roller
4. Let your other leg hang relaxed or on the ground
5. Grab the handles
6. Keep your back against the backrest

Implementation

1. Stretch your working leg
2. Push the roller up by stretching your knee
3. Extend fully to horizontal
4. Tighten your quadriceps to the max
5. Hold for 1-2 seconds
6. Release controlled (4-5 seconds)
7. Bend to about 90 degrees
8. Complete all repetitions before switching

Points of interest

• ✓ Focus on full knee extension
• ✓ Tighten your quad to the max at the top
• ✓ Slow negative phase (4-5 seconds)
• ✓ Stay symmetrical in the machine
• ✓ Keep your other leg relaxed
• ✓ Breathe out on stretching, in on bending
• ✗ Avoid offsetting with your torso
• ✗ Do not rotate at an angle in the seat
• ✗ Don't use momentum
• ✗ Don't start with too heavy a weight (lighter than bilateral)
• ✗ Don't drop down quickly
• ✗ Don't tighten your other leg

When this exercise?

This exercise is suitable for identifying and correcting quad strength differences between left and right. Ideal in rehabilitation after unilateral knee injuries to specifically strengthen the affected leg (in consultation with physiotherapist). Very effective after cruciate ligament reconstruction or meniscus surgery. Perfect for preventing stronger leg from compensating. Also valuable for bodybuilders who want to correct asymmetry. Start with 40-50% of bilateral weight.