The Boundary Between a Sit-Up and a Crunch
The sit-up and the crunch are commonly performed exercises for targeting the rectus abdominis (RA) muscles, AKA the six-pack muscles . . .
Author: Susan Cashdollar
The sit-up and the crunch are commonly performed exercises for targeting the rectus abdominis (RA) muscles, AKA the six-pack muscles . . .
