The two most important muscles of male abs for aesthetic purposes are the rectus abdominis, i.e., the classic "six-pack", and the obliques, which wrap around the sides of the waist.
Any time you do an exercise that targets the rectus abdominis, you're targeting both your "upper" and your "lower" abs - you're just targeting them from different angles.
The bicycle maneuver, which is performed without ab exercise equipment was one of the most effective effective exercises for both the rectus abdominus and the obliques.
The plank exercise engages the entire core, including the deep muscles of your abdomen, the transverse abdominis and the "six pack" muscles, the rectus abdominis.
The area that runs down the front center of the abdominal region is the rectus abdominis, and it is the muscle primarily responsible for a "six pack."
The primary function of the muscle group is to extend the knee and straighten the leg, but the rectus femoris also assists in the flexion of the hips.
Your abdominal region is made up of several muscles including the rectus abdominis, the transverse abdominis, and the internal and external obliques.
Your abdominal muscles consist of four different muscle groups, the rectus abdominis, internal obliques, external obliques and transverse abdominis.
Both are supplied by the abducens nerve, together with the rectus externus muscle.
Birgus dispenses with a covering; Coenobita can make shift with half the shell of a coco-nut; Chlaenopagurus wraps itself up in a blanket of colonial polyps; Cancellus tanneri, Faxon, was found in a piece of dead coral rock; Xylopagurus rectus, A.