At a glance
- Main muscle
- Quads
- Equipment
- Machine
- Rep range in Mitta
- 10 to 15 reps
- Skill level
- Beginner
- How tiring
- Low
- One side at a time
- Yes
- Weight step in Mitta
- 2.5 kg
How to do it
- Line the machine’s pivot up with your knee.
- One leg at a time, the other rests.
- Lean back slightly and lower all the way into the stretch.
Pick a weight you can lift for 10 to 15 reps with good form, and stop each set with a few reps left in the tank. Do the same number of reps on both sides, starting with your weaker side.
Why rating A
Same stimulus as the leg extension (including the rectus femoris), but one leg at a time: useful for left-right differences or after an injury.1,2,3
Mitta rates every exercise from S to C, based on research where it exists and on how the exercise loads the muscle. When Mitta builds your plan it picks from S, A and B exercises and prefers ones that load the muscle at long length. C exercises are never picked automatically, but you can still choose them yourself.
Alternatives
These train the same muscle. Use one if you lack the equipment, if this exercise does not feel right, or for some variety.
- Leg Extension · Machine · rating A
- Sissy Squat · Bodyweight · rating B
- Reverse Nordic · Bodyweight · rating B
Keep learning
- What is progressive overload, and how do you do it?
- How many sets per muscle per week?
- What is RIR, and how do you estimate it?
- One-rep max calculator: your max from any hard set of the single-leg leg extension.
Let Mitta set the weight.
Mitta plans the single-leg leg extension with a weight and rep target for every set, worked out from your last sessions.
Questions about the
single-leg leg extension
What muscles does the single-leg leg extension work?
The single-leg leg extension mainly trains your quads.
How many reps of the single-leg leg extension should I do?
Mitta plans the single-leg leg extension at 10 to 15 reps per set. Most sets should end with only a few reps left in the tank.
What can I do instead of the single-leg leg extension?
Good alternatives that train the same muscle are the leg extension, sissy squat and reverse Nordic.
Is the single-leg leg extension good for beginners?
Yes. It is easy to learn, so it suits people who are new to lifting.
Why does the single-leg leg extension have rating A?
Same stimulus as the leg extension (including the rectus femoris), but one leg at a time: useful for left-right differences or after an injury.
Sources
- Kubo et al. 2019, EJAP (diepe vs halve squat: meer bil- en adductorengroei, quads gelijk) doi.org/10.1007/s00421-019-04181-y
- Larsen et al. 2025, J Sports Sci 43(2):210-221 (leg extension 40° vs 90° heupflexie: meer rectus-femorisgroei bij achterover leunen, vastus gelijk; ongetrainde mannen) doi.org/10.51224/SRXIV.407
- Larsen et al. 2025, J Sports Sci (rugleuning naar achter, 40° vs 90° heupflexie: meer RF-groei, vastus gelijk) doi.org/10.1080/02640414.2024.2444713