Invention and Making of "Power Measure", a Simple Instrument to Measure Muscular Strength : Validation of the Measurement Values
The purpose of this study was to assess the validity of the measurement values obtained from "Power Measure", a simple muscular strength measuring instrument that we have developed. This instrument consists of two acrylic outer and inner cylinders with internal diameters of 9.5 cm and 8.5 cm, respectively, and one of three kinds of compression coil spring. To assess the validity of the measurement values, a weight was loaded on the instrument perpendicularly, and the compression distance of the spring corresponding to the load of the weight was defined as the actual measurement value, while the value obtained by dividing the loaded weight by the spring constant was defined as the reference value for the measurement. Although there were some issues regarding the measurement values, the relationship between the weight load and compression distance was strongly correlated with the reference values whichever spring was used. This indicates that the principle of this measuring instrument, estimation of muscular strength from the distance of spring compression in relation to the spring constant, is consistent with physical principles, and that the measurement values obtained from this instrument are highly valid.
- Journal of physical therapy science
Journal of physical therapy science 19(1), 9-13, 2007-06-30