By providing an unstable exercise platform, the TRNR Balance Disc requires you to recruit multiple core muscles at once to stay balanced. Beyond a great core activation and balance tool, the Balance Disc can help you increase flexibility, and coordination, as well as foot, ankle, knee, and hip joint stability. You can use it to stand, kneel and lie in a wide range of exercises, or even as a seat cushion to improve your posture and relieve your lower back pain. The Balance Disc comes with two distinctive textured sides – one with pressure points to deliver a stimulating massage and the other with raised circular lines to prevent your hands, arms, and feet from sliding during workouts. The hand pump included makes inflation and deflation easy, letting you quickly adjust the level of instability to best suit your needs.