An adjustable chair support system includes a first seat back support member spaced from a second seat back support member, and a seat back tensioning assembly that extends between the first and second seat back support members. The seat back tensioning assembly includes a carrier coupled to the first seat back support member, the carrier including an adjustable tension member and a first guide member, a pair of second guide members coupled to the second seat back support member, and a cable extending from the adjustable tension member into engagement with one of the pair of second guide members, with the first guide member, with the other of the pair of second guide members, and then returning to the adjustable tension member.