The alternating sit-through with crunch is a full-body movement that starts in a bear crawl position and ends with a leg kicked out to the side. In between reps, you perform a crunch. It is commonly performed for reps or time in bodyweight circuits and animal-style flows, but can also work on its own or as part of a dynamic warm-up or mobility sequence.
Builds strength and size in the shoulders and chest
Increases core strength and stability
Trains shoulder extension and stability
Greater challenge to the rectus abdominis or "six-pack" muscles than traditional sit-throughs