A sensor unit installed in a premises for detecting a user's walking behavior. Connected to the server through a communication network are a server, an information reporting unit, and an exercise machine. The server includes a diagnosis section for analyzing time series data of walking signal from the sensor unit to determine walking ability and generate walking ability data indicative thereof, and an information providing section which provides the walking ability date to the information reporting unit and the exercise machine. The information reporting unit includes reporting means for reporting the determined walking ability to the user. The exercise machine includes a control section which gives an exercise to the user depending upon the walking ability.