Risk-of-falling determination apparatus, risk-of-falling determination method, recording medium, and output apparatus

A risk-of-falling determination method comprising:

• obtaining, using a walk information obtainer, walk information of a user for a predetermined time interval, the walk information including a plurality of steps of the user;
• measuring, using a myoelectric sensor, first myoelectric potential differences by using first electrodes configured to be disposed on an anterior surface of a thigh of a leg of the user and second myoelectric potential differences by using second electrodes configured to be disposed on a posterior surface of the thigh of the leg of the user;
• excluding, using a control circuit, a first step of the user and a last step of the user from the predetermined time interval to obtain a period of steady walking of the user, the first step of the user and the last step of the user being included in the plurality of steps of the walk information of the user;
• identifying, using the control circuit, an interval of a stance phase in the predetermined time interval by using the walk information of the user, the interval of the stance phase being an interval for which a foot of the leg of the user is in contact with ground, the interval of the stance phase being included in the period of steady walking of the user;
• calculating, using the control circuit, a degree of co-contraction of a muscle at the leg of the user by using the first myoelectric potential differences for the interval of the stance phase and the second myoelectric potential differences for the interval of the stance phase, the co-contraction being simultaneous activation of a muscle near the anterior surface of the thigh of the leg and a muscle near the posterior surface of the thigh of the leg;
• comparing, using the control circuit, the degree of co-contraction to a first threshold;
• and
• outputting, using an outputter, a signal indicating that the user has a high risk of falling when the degree of co-contraction is greater than or equal to the first threshold.

A recording medium storing a control program for causing a device including a processor to perform a process, the recording medium being a non-volatile computer-readable recording medium, the process comprising:

• obtaining, using a walk information obtainer, walk information of a user for a predetermined time interval, the walk information including a plurality of steps of the user;
• measuring, using a myoelectric sensor, first myoelectric potential differences by using first electrodes configured to be disposed on an anterior surface of a thigh of a leg of the user and second myoelectric potential differences by using second electrodes configured to be disposed on a posterior surface of the thigh of the leg of the user;
• excluding, using a control circuit, a first step of the user and a last step of the user from the predetermined time interval to obtain a period of steady walking of the user, the first step of the user and the last step of the user being included in the plurality of steps of the walk information of the user;
• identifying, using the control circuit, an interval of a stance phase in the predetermined time interval by using the walk information of the user, the interval of the stance phase being an interval for which a foot of the leg of the user is in contact with ground, the interval of the stance phase being included in the period of steady walking of the user;
• calculating, using the control circuit, a degree of co-contraction of a muscle at the leg of the user by using the first myoelectric potential differences for the interval of the stance phase and the second myoelectric potential differences for the interval of the stance phase, the co-contraction being simultaneous activation of a muscle near the anterior surface of the thigh of the leg and a muscle near the posterior surface of the thigh of the leg;
• comparing, using the control circuit, the degree of co-contraction to a first threshold;
• and
• outputting, using an outputter, a signal indicating that the user has a high risk of falling when the degree of co-contraction is greater than or equal to the first threshold.