Exercise · form guide
Leg Extension
- Primary muscle
- Quads (all 4 heads
- Also works
- rectus femoris emphasis)
- Equipment
- Leg Extension Machine
- Difficulty
- Beginner
Tempo
1-2-2-0
The 2-second squeeze at full extension is everything. Slight toe rotation outward = vastus medialis (teardrop) emphasis.
Sets & reps
General programming defaults by goal — not specific to this lift. Pick the row that matches yours.
| Goal | Sets | Reps | RPE | Rest |
|---|---|---|---|---|
| Strength | 4–6 | 3–5 | 8–9 | 3–5 min |
| Hypertrophy | 3–5 | 8–12 | 7–9 | 90–120 s |
| Endurance | 2–4 | 15–25 | 6–8 | 45–60 s |
Form
Cues
- Pad just above ankle
- Full extension — squeeze 2 seconds
- Controlled descent — fight the weight
Common mistakes
- Bouncing weight at the bottom
- Half-reps from joint angle
Injury notes
Great for VMO development post-knee injury. Use light weight.
Progression
Volume first. 3 sets of 12–15. Add 2.5kg when reps land easy.
Indian gym reality
Machines vary wildly across Indian gyms — the same exercise on a different brand can feel completely different. Trust the movement pattern and target muscle, not the sticker on the machine.
If your gym doesn't have this equipment
- Use the free-weight version of the same pattern; the machine's guidance is convenience, not necessity.
Home & hostel version
Bulgarian split squats with a chair for the back foot work for months, then load them with a backpack.
Nutrition & recovery around this lift
Isolations recover fast — 24 hours is usually enough. You can hit the same muscle again the next day with a different exercise. For an Indian lifter, land 30–40g of protein within 90 minutes of finishing — 200g paneer, 4 whole eggs, 150g chicken, or a whey shake all work.
Frequently asked
What muscles does Leg Extension work?
Primarily Quads (all 4 heads, rectus femoris emphasis). Load and rep range shift the emphasis — heavy triples bias the primary mover, sets of 12+ bring more of the secondaries in.
How many sets of Leg Extension per week?
For hypertrophy, 10–20 direct working sets per week across all exercises for that muscle. This exercise usually contributes 3–8 of those sets, depending on where it sits in your program.
My Indian gym doesn't have this machine — what do I do?
See the "If your gym doesn't have this equipment" section above — every variant listed is a legitimate substitute, not a compromise.
How often should I do Leg Extension?
Most intermediates do best with 2× per week frequency on any given lift — one heavier session and one lighter, or two matched sessions with different rep ranges. Beginners can add a third if recovery holds up.
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