Used to perform different types of exercises to improve posture, cardio endurance, strength and balance. They can also be used to treat or prevent Used to perform different types of exercises to improve posture, cardio endurance, strength and balance. They can also be used to treat or prevent back discomfort caused by muscle imbalances and weak core, primarily by focusing on movements such as push-ups, planks, and sit-ups on an unstable surface.back discomfort caused by muscle imbalances and weak core, primarily by focusing on movements such as push-ups, planks, and sit-ups on an unstable surface.