Unique design that improves the effectiveness of ab exercises and helps to engage and strengthen muscles in the back, chest, arms, and core. Unlike traditional ab wheels, the BodyPro Ab Roller Professional is an ab wheel with uses a unique carbon steel spring mechanism that provides resistance as users roll out and assistance as they roll back, engaging muscles more thoroughly. While most ab rollers feature flat wheels that only allow for rolling straight out and back, the Ab Roller Pro features a wide, spherical wheel that helps users engage all ab muscles, including obliques, by pivoting to the right and left. This helps to strengthen deep core muscles that stabilize the pelvis and spine. The Ab Roller Professional also features padded, angled, ergonomic hand grips that maximize engagement of arm muscles while remaining comfortable and stable.