Customizable chair with multipoint adjustment

A chair comprising:

• a seat member for supporting a user;
• a backrest member attached to a back portion of the seat member, the backrest member having a plurality of longitudinally aligned holes formed therethrough, the holes being disposed along a center portion of the backrest member;
• an elongate band attached to the backrest member aligned with the plurality of longitudinally aligned holes, one end of the elongate band being fixedly attached to the backrest member and an opposing end of the elongate band being movably coupled to the backrest member;
• a plurality of curve adjusting screws corresponding to the plurality of holes, the screws extending through respective holes so that the screws contact the elongate band and can be selectively adjusted to provide a selected curvature to the elongate band;
• and
• an auditory or tactile feedback device attached to an upper portion of the backrest member and aligned with the elongate band so that when a force is applied to an upper portion of the band by a user performing an axial extension exercise, the feedback device provides an audible or tactile signal to a user.

A chair comprising:

• a seat member for supporting a user;
• a backrest member mounted on the seat member;
• an adjustable platform attached to the backrest member, the adjustable platform being selectively adjustable to provide a desired contour for supporting the back of a user seated within the chair;
• and
• an adjustment mechanism configured to adjust the adjustable platform along one or more locations of the platform to provide a desired contour for supporting the back of a user seated within the chair;
• wherein the adjustable platform comprises an elongate band attached to the backrest member and disposed over a central longitudinal axis of the backrest member, one end of the elongate band being attached to the backrest member and an opposite end of the elongate band being slidably attached relative to the backrest member.