Crunches

Isolation abdominal exercise targeting the rectus abdominis through controlled spinal flexion with minimal hip flexor involvement.

Instructions

1. Lie flat on your back with your feet flat on the ground and your knees bent at approximately 90 degrees. Alternatively, rest your feet on a bench with knees bent at 90 degrees; if using a bench, place feet 3-4 inches apart and point your toes inward.
2. Place your hands lightly on either side of your head near your ears, keeping your elbows out to the sides. Do not lock your fingers behind your head.
3. Push the small of your back down into the floor to isolate your abdominal muscles.
4. Contract your abdominals and exhale as you roll your shoulders off the floor. Only your shoulders should come up off the floor, approximately 4 inches; your lower back should remain on the floor.
5. At the top of the movement, contract your abdominals hard and hold the contraction for a second.
6. After one second, begin to come down slowly to the starting position as you inhale.
7. Repeat for the recommended amount of repetitions.

Tips

• Focus on slow, controlled movements; avoid using momentum to cheat the movement.
• Keep your lower back in contact with the floor throughout the entire exercise.
• Only lift your shoulders approximately 4 inches off the floor; full sit-ups involve more hip flexor activation.
• Avoid pulling on your neck; hands are only for light support.
• Breathe out as you contract upward and breathe in as you lower yourself.
• This exercise isolates the abdominals more effectively than full sit-ups.
• Progress by adding resistance (holding a plate) or increasing reps before changing exercises.