A detection device for detecting the posture and movement of a user, comprising: i) a main body, wherein the main body is an insole insertable into a footwear; ii) a detection group that is embedded in the main body and comprises at least one detection member comprising at least one accelerometer element and at least one gyroscope element; iii) a power supply group that is embedded in the main body and is operatively connected to the detection group in order to supply electricity thereto, wherein the power supply group comprises: - a generator organ of alternating current substantially disc-shaped, comprising a main axis (X-X), an imaginary plane on which it extends substantially orthogonally to the main axis (X-X), and comprising a rotary element having an eccentric shape with respect to said main axis (X-X), suitable for rotating freely when subjected to movement, wherein said main axis X-X is inclined by a few degrees with respect to the vertical, wherein the generator organ of alternating current comprises a rotor and a stator, wherein said rotor is operatively connected to said rotary element; - a generator organ of direct current, which is electrically connected to the generator organ of alternating current that receives the alternating current and transforms it into direct current in order to supply electricity to the detection group. i) a main body, wherein the main body is an insole insertable into a footwear; ii) a detection group that is embedded in the main body and comprises at least one detection member comprising at least one accelerometer element and at least one gyroscope element; iii) a power supply group that is embedded in the main body and is operatively connected to the detection group in order to supply electricity thereto, wherein the power supply group comprises: - a generator organ of alternating current substantially disc-shaped, comprising a main axis (X-X), an imaginary plane on which it extends substantially orthogonally to the main axis (X-X), and comprising a rotary element having an eccentric shape with respect to said main axis (X-X), suitable for rotating freely when subjected to movement, wherein said main axis X-X is inclined by a few degrees with respect to the vertical, wherein the generator organ of alternating current comprises a rotor and a stator, wherein said rotor is operatively connected to said rotary element; - a generator organ of direct current, which is electrically connected to the generator organ of alternating current that receives the alternating current and transforms it into direct current in order to supply electricity to the detection group. - a generator organ of alternating current substantially disc-shaped, comprising a main axis (X-X), an imaginary plane on which it extends substantially orthogonally to the main axis (X-X), and comprising a rotary element having an eccentric shape with respect to said main axis (X-X), suitable for rotating freely when subjected to movement, wherein said main axis X-X is inclined by a few degrees with respect to the vertical, wherein the generator organ of alternating current comprises a rotor and a stator, wherein said rotor is operatively connected to said rotary element; - a generator organ of direct current, which is electrically connected to the generator organ of alternating current that receives the alternating current and transforms it into direct current in order to supply electricity to the detection group.