A chair strengthens core muscle groups and promotes circulation along the gluteal and piriformis muscle groups. Locking castors enable the chair to be moved in busy environments, yet fix the position of the chair when needed. A user of the chair may activate a number of massaging elements by rocking side to side, and may perform back stretches while in the seated position. Additional active massaging elements may alert the user and further promote proper use. Adjustable elements allow users to tailor the chair to their specific needs. Embedded energy harvesters supply power to record and transmit data to users to enhance their awareness of their seating position. Thus a versatile seat is provided that is better suited to active environments while broadening the range of elements of core strengthening, massaging, circulation, and seated exercise.