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Single-Leg Leg Extension

Performed unilaterally with one leg to correct imbalances, this variation primarily targets your Quadriceps. It requires machine and is best suited to beginner lifters.

Beginner level · Equipment: Machine · Isolation · Push

Primary muscles: Quadriceps

How to perform Single-Leg Leg Extension

  1. Step 1. Seat yourself in the machine and adjust it so that you are positioned properly. The pad should be against the lower part of the shin but not in contact with the ankle. Adjust the seat so that the pivot point is in line with your knee. Select a weight appropriate for your abilities.
  2. Step 2. Maintaining good posture, fully extend one leg, pausing at the top of the motion.
  3. Step 3. Return to the starting position without letting the weight stop, keeping tension on the muscle.
  4. Step 4. Repeat for the desired number of repetitions.

Frequently asked questions

What are the primary muscles targeted by the single-leg leg extension?

This isolation exercise specifically targets the quadriceps. By working one leg at a time, you can better address muscular imbalances and improve mind-muscle connection with each thigh.

How should I position my body to ensure proper form?

Align your knee joint with the machine's pivot point and press your lower back firmly against the seat. Keep your toes pointed upward or slightly outward to maintain tension throughout the quadriceps.

What is a common mistake to avoid during the movement?

Avoid using momentum or allowing your hips to lift off the seat during the concentric phase. Ensure the movement is controlled and that the non-working leg remains relaxed and stationary.

How can a beginner progress with this exercise?

Start with a light weight to master the range of motion and focus on a one-second pause at the top of the lift. Once comfortable, gradually increase the load while maintaining a controlled eccentric phase.

What is the recommended set and rep range for hypertrophy?

Perform 3 to 4 sets of 10 to 15 repetitions per leg. This higher rep range is effective for accumulating metabolic stress in the quadriceps while minimizing joint strain.

Sample sets & reps for Single-Leg Leg Extension

  • Form first: 3 sets × 10-12 reps, 60s rest. RPE 6, focus on the target muscle.
  • Hypertrophy: 3 sets × 12-15 reps, 45-60s rest. RPE 7-8, controlled eccentric.
  • Burnout finisher: 2 sets × 15-20 reps, 45s rest. RPE 9, last set to failure.

Pick the scheme that matches your goal. Beginners should start at the lower end of every range; progress weight only when you hit the upper end of the rep range with one or two reps in reserve.

Related Quadriceps exercises

  • All Fours Quad Stretch — stretch
  • Alternate Leg Diagonal Bound — other
  • Backward Drag — other
  • Barbell Full Squat — barbell
  • Barbell Hack Squat — barbell

See all Quadriceps exercises →

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