The leg extension isolates the quads by straightening the knee against resistance from a seated position. It is a simple way to add quad volume and works well for finishing off a leg session.
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3
Sets
15
Reps
Machine
Equipment
6.00
Cal/min
🎯 Muscles Worked
🎯
Primary
Quads
📋 How To Perform Leg Extension
1
Sit in the machine, pad resting just above your ankles, knees at 90°.
2
Grip the side handles for stability.
3
Extend your legs until they're straight, squeezing your quads at the top.
4
Lower slowly back down under control.
5
Avoid locking your knees out violently — control the top of the movement.
💡 Benefits of Leg Extension
Isolates all four heads of the quadriceps, including the rectus femoris, without needing to balance. It is useful for building quad size and for lifters who cannot squat heavy.
📈 Sets, Reps & Programming
Do 3 sets of 12 to 20 reps with a one-second squeeze at the top. Adjust the pad above the ankles and the backrest so the knees line up with the machine pivot.
⚠️ Common Mistakes to Avoid
Swinging the weight up with momentum
Locking the knees violently at the top
Lifting the hips off the seat
✅ Pro Tips
Squeeze the quads hard for a second at the top
Lower under control rather than dropping the weight
🛡️ Safety Notes
The load on the knee joint can bother people with patellar issues. Use moderate weights, avoid very heavy loads and stop if you feel front-knee pain.
🔁 Progressions & Regressions
Make it hardersingle-leg extension or a slow tempo.
