Leg Extension
Skip the guesswork: Leg Extension leans on a fixed machine groove for quad size and knee resilience.
How to do Leg Extension
- For this exercise you will need to use a leg extension machine. First choose your weight and sit on the machine with your legs under the pad (feet pointed forward) and the hands holding the side bars. This will be your starting position. Tip: You will need to adjust the pad so that it falls on top of your lower leg (just above your feet). Also, make sure that your legs form a 90-degree angle between the lower and upper leg. If the angle is less than 90-degrees then that means the knee is over the toes which in turn creates undue stress at the knee joint. If the machine is designed that way, either look for another machine or just make sure that when you start executing the exercise you stop going down once you hit the 90-degree angle.
- Using your quadriceps, extend your legs to the maximum as you exhale. Ensure that the rest of the body remains stationary on the seat. Pause a second on the contracted position.
- Slowly lower the weight back to the original position as you inhale, ensuring that you do not go past the 90-degree angle limit.
- Repeat for the recommended amount of times.
Leg Extension Sets and Reps by Goal
Strength
3 sets of 5-6 reps with 2-3 minutes of rest. Add one plate only when the full range stays smooth.
Hypertrophy
3 sets of 10-12 reps with 90 seconds of rest. Control the return instead of letting the stack drop.
Endurance
2-3 sets of 15-18 reps with 45-60 seconds of rest. Match the seat and pad settings every session.
Common Leg Extension Mistakes
Letting the weight stack crash on the way back
Control the return for the same count as the working phase.
Letting the knees cave inward as fatigue builds
Press the outside edge of each foot into the floor throughout.
Training every set to failure this early
Leave two or three reps in the tank and add sets instead.
Easier and Harder Than Leg Extension
Swap Leg Extension For
Leg Extension — Frequently Asked Questions
How do you do the Leg Extension?
For this exercise you will need to use a leg extension machine. First choose your weight and sit on the machine with your legs under the pad (feet pointed forward) and the hands holding the side bars. This will be your starting position. Tip: You will need to adjust the pad so that it falls on top of your lower leg (just above your feet). Also, make sure that your legs form a 90-degree angle between the lower and upper leg. If the angle is less than 90-degrees then that means the knee is over the toes which in turn creates undue stress at the knee joint. If the machine is designed that way, either look for another machine or just make sure that when you start executing the exercise you stop going down once you hit the 90-degree angle. Using your quadriceps, extend your legs to the maximum as you exhale. Ensure that the rest of the body remains stationary on the seat. Pause a second on the contracted position. Slowly lower the weight back to the original position as you inhale, ensuring that you do not go past the 90-degree angle limit. Use a leverage machine and keep the movement controlled through the full range. The animated GIF above shows the complete rep at normal speed.
What muscles does the Leg Extension work?
The Leg Extension primarily targets the quads. It is classified as a legs exercise and is performed with a leverage machine.
How many sets and reps of the Leg Extension should I do?
For muscle growth: 3 sets of 10-12 reps with 90 seconds of rest. Control the return instead of letting the stack drop. Adjust the load rather than the rep target if form breaks down before the final rep.
Is the Leg Extension good for beginners?
Yes. The Leg Extension is a beginner-level movement, so it is a reasonable place to start. Keep the load light enough that you can control every rep and stop 2-3 reps short of failure while you learn the pattern.
What can I do instead of the Leg Extension?
Try the Barbell Clean And Press, Suspended Split Squat or the Dumbbell Lunge. Each trains the quads with a similar movement pattern, so you can swap based on the equipment you have available.
