Sit upright in the leg extension machine and position your legs under the pad.
2. Grab the side handles for additional support. Right now your knees should be flexed to 90 degrees and your lower back and shoulders should be in contact with the back pad.
3. Extend your legs until your shins are aligned with your thighs.
4. Hold the contraction for a moment and slowly flex your knees back to the starting position.
Working muscle/muscles:
