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Exercise Guide
How to do one leg extension
Master the setup, range of motion, and tempo for safer, more effective reps.
The one-leg extension is a unilateral isolation exercise that primarily targets the quadriceps muscles. By working one leg at a time, you can effectively address muscle imbalances and ensure equal strength development across both limbs. This movement is performed on a leg extension machine and is highly effective for isolating the front of the thigh without engaging the glutes or hamstrings.
Stats
TIER
1
DIFFICULTY
Intermediate to Advanced
EQUIPMENT
Leg Extension
TARGET MUSCLES
Quads
Instructions for Proper Form
Setup:
- Machine Adjustment: Adjust the seat back and foot pad on the leg extension machine so that your knee aligns with the machine's axis.
- Starting Position: Sit with your back against the backrest and one foot positioned behind the padded lever. Your knee should be bent at a 90-degree angle. Your other leg can either rest on the floor or be crossed over the working leg.
The Lift:
- Extend the Leg: Exhale and extend your knee, lifting the lever until your leg is almost straight. Avoid locking out your knee at the top.
- Hold and Squeeze: Pause briefly at the top of the movement, squeezing your quadriceps muscles.
- Controlled Lowering: Inhale and slowly lower the weight back to the starting position, resisting the weight as it comes down.
- Repeat: Perform the desired number of repetitions, then switch legs.
Tips:
- Focus on the Quadriceps: Concentrate on the feeling of your quadriceps muscle working throughout the movement.
- Maintain Back Contact: Keep your back pressed firmly against the backrest throughout the exercise.
- Smooth Movement: Avoid jerking or bouncing the weight. The movement should be smooth and controlled.
Common mistakes: Lifting the hips off the seat to leverage more weight, locking the knee too forcefully at the top, and using momentum rather than muscle contraction.
Alternatives
Leg Extension
one leg extension
Quads
Leg Extension
leg extension
QuadsGlutes
Barbell
barbell squat
QuadsGlutes
Leg Press
seated leg press
QuadsGlutes
Squat Rack
barbell front squat
QuadsGlutes
Bench
barbell bulgarian split squat
QuadsGlutes
Barbell
barbell box squat
QuadsGlutes
Hack Squat Machine
hack squat
QuadsGlutes
None
forward lunge
Quads
Kettlebell
kettlebell front squat
QuadsGlutes
Kettlebell
kettlebell goblet squat
QuadsGlutes
None
rear lunge
QuadsGlutes
Kettlebell
kettlebell one arm swing
QuadsGlutes+2
Kettlebell
kettlebell thruster
QuadsGlutes+5
Barbell
barbell overhead squat
QuadsGlutes
Barbell
barbell zercher squat
QuadsGlutes
Barbell
barbell overhead lunge
QuadsGlutes+1
Leg Press
squat calf raise on legpress
QuadsGlutes+1
None
step up with chair
QuadsGlutes+1
Dumbbell
dumbbell swing
QuadsHamstrings+3
Dumbbell
dumbbell thruster
QuadsGlutes+4
Smith Machine
smith-machine leg press
QuadsGlutes
Bench
sissy squat
QuadsGlutes
Smith Machine
smit-machine split squat
QuadsGlutes
Hack Squat Machine
reverse hack squat
QuadsGlutes
Smith Machine
smit-machine squat
QuadsGlutes
Dumbbell
dumbbell lunge
QuadsGlutes
Pendulum Squat Machine
pendulum squat
QuadsGlutes
None
pistol squat
QuadsGlutes
Sled Leg Press
sled 45° leg press
QuadsGlutes
Tread Mill
run on treadmill
QuadsGlutes+1
None
run
QuadsGlutes+1
Assault Runner
assault run
QuadsHamstrings+2
Ski Trainer
ski trainer
QuadsGlutes+3
Barbell
barbell thruster
QuadsGlutes+4
Assault Bike
assault bike run
QuadsHamstrings+6