PROBLEM TO BE SOLVED: To provide an activity information meter which is capable of stable transmission between a measuring device and an output device and is highly convenient.SOLUTION: In a measuring device 1 or 101 and an output device 51 or 151, a selector is placed between a current output section and each electrode and between a voltage detection section and at least one electrode and a transmission route is selected as appropriate, thereby making possible bidirectional transmission using a body as a medium, a change in potential is detected based on a reference potential at the time of reception without using the earth as a reference potential or a voltage generated based on a body part impedance is detected without using the earth as a reference potential. As a result, the activity information meter is hardly influenced by the environment.COPYRIGHT: (C)2008,JPO&INPIT【課題】測定器と出力器との間における通信が安定し、利便性の高い活動情報計を提供する。【解決手段】測定器1又は101及び出力器51又は151の各々において、電流出力部と各電極との間、及び電圧検出部と少なくとも一つの電極との間にセレクタを配置して、適宜、通信経路を選択することによって、身体を媒体としての双方向の通信を可能とし、また、大地アースを基準電位とせずに、受信の際に基づいて基準電位を基準とした電位変化を検出し、又は大地アースを基準電位とせずに、身体部位インピーダンスに基づいて生ずる電圧を検出するもので、これよって、環境などによる影響を受けないものとした。【選択図】図1
