Information on daily physical activity is essential for determining daily nutritional demands and devising physical conditioning programs. In order to obtain reliable information on daily physical activity, it is necessary to record the activity in some way. Up to now, however, such data have been collected using retrospective questionnaires and observation, and by measurement of heart rate over extensive periods. These methods are too cumbersome and expensive.
The purpose of the present study was to develop a new device for recording physical activity in the form of an actogram. A pedometer was used to record the physical activity, and a microswitch was set inside the pedometer to convert the pedometer count into an electric signal, since it is advantageous to process the data by computer. The pedometer count was recorded in the IC memory of a computer with a 32-kbyte. The memorized pedometer count was fed into the personal computer through an interface, and after processing it was displayed as an actogram representing the activity pattern and the amount of physical activity.
The new device developed in this study could serve as a practical tool for recording the quantity and time course of physical activity during daily life, since it is small (110mm×70 mm×30 mm) and light (170g), less expensive and also convenient to handle.
