Provided herein are exemplary embodiments of a weighing device comprising a bladder and a plurality of contact switches printed on the bladder. The bladder comprises a top and a bottom sheet of a suitable non porous material. The contact switches are made by printing a conductive pattern on one side of the bladder and printing conductive elements with leads or traces on the other side of the bladder. The two sides of the bladder are heat sealed together along the periphery of the bladder with the conductive portions facing each other. An inflation port is also formed in the periphery. In operation, the bladder is placed under an individual to be weighed. Next, the bladder is inflated using a gas. Finally, monitoring circuitry coupled to the bladder measures and records the pressure at the time each of the switches open due to the separation of the conductive portions.