EVALUATION OF 2 INSTRUMENTS FOR RECORDING SITTING AND STANDING POSTURES AND NUMBER OF FOOT STEPS

The study evaluates two simple instruments that may be used to describ e aspects of physical workload in almost any occupation: a pedometer, which measures the number of steps taken by the subject wearing it, an d a posimeter, which quantifies the time spent sitting and the number of changes between sitting and an upright position. The present data s howed that the pedometer registers the correct number of steps at 'ord inary' walking speed independent of type of floor (plastic carpet and stone floor), shoes (wooden shoes and sneakers) and gender. At 'slow' walking (2.4 km/h) a reduced number of steps was recorded. In a field study the median difference between pedometer registration and observa tion was 6% (range 1-27) of the observed number of steps. The range of pedometer variation in relation to the mean value obtained for the fi ve investigated pedometers was 0-15%. The posimeter was found to give a good estimate of the percentage time spent sitting (mean deviation 3 %, range 0-15%). The number of changes between sitting and standing wa s overestimated by the posimeter (median deviation 63% of the observed ). Some extreme working postures can be misread by the posimeter.