New chromophore for phytic acid determination

An exercising device for strengthening hands or limbs has first and second bladders containing fluid with first and second valves that couple the bladders to a fluid pressure gage. Squeezing the first bladder by the left hand causes easy flow through the first valve to the pressure gage in a first direction, whereas the second valve presents a high impedance to flow in the same direction into the right hand bladder, so that the measured gage impulse pressure is proportional to the flow rate of fluid through the second valve indicating left hand strength. Squeezing the second bladder by the right hand produces fluid flow in the opposite direction with the right hand strength being measured in like manner. Alternate bladder squeezing creates a pleasant rhythmic exercise routine and the peak gage pressure indicates progress. The valve configuration enables strength measurement of the weak and the strong with one device.