Core body fitness
Training the core is more just about developing six-pack muscles and endless sets of sit-ups.
The core also consists of muscles deep within the abs and back and is brings stability and balance to the entire body. It's where our body movement originates from and effective core training has many positive results, from improved posture and reduced risk of injury, to better athletic performance in all sports.
The most effective abdominal equipment are those that don't target the abs in isolation but seek to train the core body muscles as an integrated unit.