A chair for providing support to a user's spine to improve posture and for providing ways for the user to perform exercises. The chair may include a flexible connection that enables a back support to move side to side through a sidebending range of motion of the user. The back support, which may include a flexible chair spine, may be configured to adapt to the curvature of the user's spine when the user is seated in the chair. A seat of the chair may include channels and vents to improve air circulation within the seat.