Leg Extension Machine

Purpose of the exercise

Isolation exercise for the quadriceps (all four heads: rectus femoris, vastus lateralis, vastus medialis, vastus intermedius). Improves quadriceps strength and mass, develops knee extension strength and helps isolate weak quadriceps after injuries. Also effective for VMO activation and for aesthetic quad development.

Supplies

• Leg extension machine
• No further material required

Starting position

1. Sit in the leg extension machine
2. Adjust the backrest so that your knee is at the end of the seat
3. Place your ankles under the pad/rollers
4. Set the weight on the stack
5. Grasp the handles next to your hips
6. Keep your back against the backrest
7. Feet at hip width

Implementation

1. Stretch both legs at the same time
2. Push the rollers up by stretching your knees
3. Fully extend until your legs are horizontal
4. Tighten your quadriceps to the max at the top
5. Hold for 1 second in full extension
6. Release controlled back to the starting position
7. Bend your knees to about 90 degrees
8. Repeat the movement without stopping at the bottom

Points of interest

• ✓ Fully extend your knees at the top
• ✓ Tighten your quadriceps to the max in end position
• ✓ Move in a controlled manner, especially when lowering (3-4 seconds)
• ✓ Keep your back against the backrest
• ✓ Stay seated (don't lift your buttocks)
• ✓ Breathe out on stretching, in on bending
• ✗ Avoid swinging or using momentum
• ✗ Don't stretch halfway - full range of motion important
• ✗ Don't drop down quickly
• ✗ Don't use too heavy weight (increases knee stress)
• ✗ Don't lift your buttocks from the seat
• ✗ Do not go further back than 90 degrees of knee flexion

When this exercise?

This exercise is suitable as an isolation exercise for quadriceps development or in rehabilitation after knee injuries when isolated quad strengthening is desired (in consultation with physiotherapist). Ideal as an accessory exercise after compound leg work (squats). Highly effective for VMO activation and quad hypertrophy. Perfect for bodybuilders looking to improve quad-shape. Also valuable as a finishing exercise to fully deplete quadriceps. IMPORTANT: There is debate about knee loading - some experts advise against for knee problems. For patellofemoral pain, patellar tendinopathy or other knee complaints, consult with physiotherapist first. Use controlled movements and not too heavy weight.