Differences between a crunch and a sit-up

Unlike the sit-up, when performing a crunch the lower back should not leave the floor. This is said to eliminate any involvement by the hip flexors, and make the crunch an effective isolation exercise for the abdominals. The difficulty of the crunch can be increased by lying on a declined bench and/or holding a weight on the chest or behind the head.

Ab Circle Pro Machine

Crunches

The crunch exercise was one of the most common exercises for the abdominal muscles in late 20th century America, said to primarily work the rectus abdominis. A safer alternative to the standard crunch is a variant of the crunch known as the curl-up, as taught by spine biomechanics professor Dr. Stuart McGill. This curl-up is considered to be a safer alternative to the crunch, which differs from the sit-up.

Ab Circle Pro

Crunch Form

Proper Form for Crunches

Proper starting form is lying face up on the floor with knees bent. The movement begins by curling the shoulders towards the pelvis, with hands placed behind or beside the neck, or crossed over the chest. Using the hands to exert force on the neck can cause injury, so common practice is to avoid placing the hands behind the head itself. The hands can however, form a shelf to support the weight of the head, so that the neck flexor muscles can relax during the movement. So long as the neck remains in an extended position with the neck flexors relaxed, then the hands are not exerting excessive force and it will not cause injury.

Related Posts:

• The Best Ab Machine
• Ab Circle Pro Review
• Ab Circle