Secure yourself into the seat and place you back against the padding.
Gripping the handles crunch forwards.
In a controlled manner return to the start position and repeat.
Common Mistakes
Using the arms to pull the weight forwards.
Lower back coming off of the back padding.
Rushing repetitions.
Where you should 'feel it':
Primary Muscles:
Abs
Secondary Muscles
Obliques
Adjust the seat height so that your shoulders are aligned with the top of the padding. Hook your feet under the foot pads and grip the handles securely.
Start the crunch by activating your core and hinge your torso forwards as far as comfortable, then slowly return to the starting position. Keep your lower back constantly against the padding. To target the obliques adjust the Repeat for the desired amount of repetitions.
Avoid using the arms to pull the weights down or rushing repetitions.