Leg Extension vs One Leg Knee Up
Which one fits your Leg workout plan?
Contents
Planfit users log Leg Extension more often — 49,848 sessions vs 1,113. Compare Leg form, muscles worked, and when to use each.
Compare the benefits of Leg Extension and One Leg Knee Up and pick the one that fits your Leg workout.
Leg Extension vs One Leg Knee Up: Which Do Planfit Users Choose?
Based on randomly selected data from 1 million completed workouts, Planfit users log Leg Extension more often — 49,848 sessions compared to 1,113 for One Leg Knee Up.
What most people do isn't always what fits you. Leg Extension and One Leg Knee Up differ in the muscles they work, the equipment they need, and how hard they are to learn — the comparison below covers each.
How Leg Extension and One Leg Knee Up Differ
| What differs | Leg Extension | One Leg Knee Up |
|---|---|---|
| Muscles worked | quads | quads, abs, and hamstrings |
| Equipment | a machine | bodyweight only |
| One side at a time | No | Yes |
| Difficulty | 1 of 5 | 2 of 5 |
| Sessions logged by Planfit users | 49,848 sessions | 1,113 sessions |
How to Do Leg Extension
Leg Extension Muscles Worked: Leg
Form
- 1. Please lift until your knees are fully extended.
- 2. Please contract from the front of your thigh close to your knee up to the upper thigh near the hip joint.
- 3. Slowly lower down until the angle of your knees is 90 degrees while resisting the weight.
Coach's Tips
- 1. Please do not give any momentum as it may injure your knees.
- 2. Please be careful not to fully bend or straighten your knees.
- 3. Please be careful not to let your hips and back separate.
For a full Leg Extension guide with alternatives and benefits, see the Leg Extension exercise guide.
How to Do One Leg Knee Up
One Leg Knee Up Muscles Worked: Leg
Form
- 1. Lift one knee forward and touch it with both hands.
- 2. Please do the same on the other side.
Coach's Tips
- Please be careful not to let your legs spread apart.
For a full One Leg Knee Up guide with alternatives and benefits, see the One Leg Knee Up exercise guide.
Frequently Asked Questions
Which is better for Leg, Leg Extension or One Leg Knee Up?
Planfit users log Leg Extension more often — 49,848 sessions against 1,113 for One Leg Knee Up. Both train Leg, so pick the one that matches the equipment you have and the muscles you want to load.
Do Leg Extension and One Leg Knee Up work the same muscles?
Not quite. Leg Extension loads quads, and One Leg Knee Up loads quads, abs, and hamstrings.
What equipment do Leg Extension and One Leg Knee Up need?
Leg Extension needs a machine, and One Leg Knee Up needs bodyweight only.
Which is easier to start with?
Leg Extension is the easier place to start. Move to One Leg Knee Up once your form holds up.
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