Exercise Library / Leg Extension
Leg Extension
The leg extension straightens your knees against resistance to strengthen the quadriceps at the front of your thighs.
Strength TrainingWhat this exercise does
The leg extension straightens your knees against resistance to strengthen the quadriceps at the front of your thighs. It isolates the muscles used to stand and climb stairs.
At a glance
- Body part
- Legs – Thighs
- Muscles worked
- Quads
- Experience
- Intermediate
- Equipment
- Weight Machines
- Good for
- Joint-Friendly / Low-Impact
How to do it
- Sit on the machine with your back against the pad and your knees lined up with the pivot.
- Set the pad over your lower shins and choose a light weight.
- Straighten your legs until they are nearly flat.
- Pause for a second.
- Lower slowly. Do 10 to 12 reps.
Common mistakes
- Swinging the weight up.
- Locking the knees hard at the top.
- Lifting your hips off the seat.
Make it easier or harder
Make it easier
Do a seated knee extension with no weight on a chair.
Make it harder
Slow the lowering to three seconds, or use one leg at a time.
Keep it safe
Use a light weight and avoid snapping the knees straight. Stop if you feel pain at the kneecap.
Related exercises
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- Type
- Strength Training
- Body area
- Legs – Thighs
- Experience
- Beginner
- Equipment
- No Equipment
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- Body area
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- Equipment
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- Body area
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- Body area
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