The resistance needs to be adequate enough to return a client to a starting position. Clients with significant extensor tone often need a firmer amount of resistance. Clients who need a lot of movement and rock tend to require light resistance. The Seating Dynamics Rocker Back includes a range of polymers to change the resistance without having to order more equipment. The Seating Dynamics footrests include a range of springs, also allowing for quick and easy resistance adjustment.