HOW TO DO MACHINE LEG EXTENSION
- Line the knee up with the machine’s cam. The pad sits on the lower shin, not the mid-foot.
- Sit so the hips stay down and the back is on the pad. Grab the handles.
- Extend until the knees are straight without kicking the stack or hyperextending.
- Lower under control into a stretch you can own — stop before the plates crash.
COMMON MISTAKES
- Pivot not at the knee. If the cam is behind or in front of the joint, every rep shears. Move the seat until the axes match.
- Swinging the weight up. A kick hides the hard part of the range. Slow the last 30° or drop the pin.
- Tiny range with a huge stack. LIFTAG will store the load. Your knees will store the habit. Own the stretch and the lockout.
- Logging extensions as squat volume. This is isolation. Hack squat, leg press, and this slug are three charts. Keep them that way.
VARIATIONS
- Standard leg press — Compound quad volume when you still want a machine.
- Machine hack squat — Sled squat if you need more than a kick.
- Barbell front squat — Upright free-weight squat with a real quad tax.
PROGRESSIONS
- Light full-range extensions with the knee on the cam.
- Pause a beat at lockout without hyperextending.
- Single-leg when one side always bails first.
- Heavier 8–12 once the seat setup is the same every session.
PROGRAMMING NOTES
Finisher, not a squat replacement: 2–4 sets of 8–15. Scan the actual machine — the tag should open this exercise. If the knees complain, shorten the bottom slightly and slow the top rather than piling plates on a bounced lockout.
EQUIPMENT ALTERNATIVES
- Standard leg press — Keep quad work when the extension machine is a queue.
- Pendulum squat — Guided compound if you want load without an isolation kick.
FREQUENTLY ASKED QUESTIONS
They are a long-lever isolation. Align the pivot, pick a range you control, and do not bounce. If a given machine always hurts, swap to hack squat or leg press and log that instead.
