Leg Extensions
The Leg Extensions isolates the Quadriceps through a controlled range of motion. This beginner-level machine exercise builds focused strength where compound movements often fall short.
Starting position
Ending position
Muscles Worked
The quadriceps handles the primary load during this movement. This isolation movement keeps tension concentrated on a single muscle group.
How to Leg Extensions
- 1
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.
- 2
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.
- 3
Slowly lower the weight back to the original position as you inhale, ensuring that you do not go past the 90-degree angle limit.
- 4
Repeat for the recommended amount of times.
Common Mistakes
- • Focus on the mind-muscle connection — feel the target muscle working through each rep.
- • Use a controlled tempo of 2 seconds up, 2 seconds down to eliminate momentum.
- • Adjust the seat height and pad positions before your working sets — proper alignment prevents joint stress.
- • Avoid locking out aggressively at the top — stop just short of full extension to keep tension on the muscle.
Similar Exercises
Frequently Asked Questions
What muscles does the Leg Extensions work?
The Leg Extensions primarily targets the Quadriceps. It's an effective isolation exercise for building quadriceps strength.
Is the Leg Extensions good for beginners?
Yes, the Leg Extensions is suitable for beginners. Start with light weight to master the 4-step form before adding load.
What equipment do I need for the Leg Extensions?
You need machine to perform the Leg Extensions. Most commercial gyms will have this available.
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