Leg Extension
Knee extension on a machine to isolate the quads.
- Primary muscleQuads
- EquipmentMachine
- TypeIsolation
- LevelBeginner
- Quads
- Machine
How to do the Leg Extension
4 steps, in the order you do them.
- Adjust the backrest so your knees line up with the machine's pivot and the pad rests on your lower shins, over your ankles.
- Grab the handles with your back against the pad.
- Extend your knees all the way up and squeeze your quads for one second.
- Lower in a controlled way without letting the plates rest.
Muscles worked
Common Leg Extension mistakes
What goes wrong most often when you do the Leg Extension, and how to fix it.
The knees sit in front of or behind the machine's pivot.
Adjust the backrest until the center of your knee lines up with the pivot.
The hips lift off the seat as you extend.
Hold the handles and push your hips into the seat throughout the lift.
You kick up and don't fully extend.
Lift until your knees are straight and hold for a second at the top before lowering.
Alternatives to the Leg Extension
They work the quads with other equipment, including options for training at home.
Sets and reps
This is how Mobbe routines program it. It appears in 4 of the 36 routines.
- Experienced3 × 12–15
- Rest1:15 to 1:30
| Routine | Level | Sets × reps | Rest |
|---|---|---|---|
| Intermediate PPL 6 Days | Intermediate | 3 × 12–15 | 1:30 |
| Quad specialization | Intermediate and advanced | 3 × 12–15 | 1:15 |
| PPL 6 days high volume | Advanced | 3 × 12–15 | 1:30 |
| Body part split 5 days | Advanced | 3 × 12–15 | 1:15 |
Rest between sets, in minutes.
Log every set and watch your numbers climb.
Mobbe saves every set, shows you your record and builds your full routine. Your first routine is free, with no limits.
Routines that include the Leg Extension
- Intermediate PPL 6 Days6 days · 70 min · IntermediateSee routine →
- Quad specialization4 days · 70 min · Intermediate and advancedSee routine →
- PPL 6 days high volume6 days · 85 min · AdvancedSee routine →
More quads exercises
Single Leg ExtensionQuads · Machine
TRX Pistol SquatQuads · Bodyweight and other
Trap Bar DeadliftQuads · Other
Smith Machine Bulgarian Split SquatQuads · Machine
Frequently asked questions
What muscles does the Leg Extension work?
The Leg Extension works mainly the quads.
How many sets and reps should I do?
In Mobbe routines the most common is 3 sets of 12 to 15 reps with 1 minute and 22.5 seconds of rest.
Which routines include the Leg Extension?
It appears in 4 of the 36 Mobbe routines, such as Intermediate PPL 6 Days, Quad specialization, and PPL 6 days high volume.