There is provided a measuring device capable of measuring a propulsion force and a loss force by using a simple method. A first detection circuit that is a bridge circuit, to which a first strain gauge and a second strain gauge disposed such that detection directions are parallel to a longitudinal direction of a crank are connected, detecting bending deformation x occurring in the crank, and a second detection circuit that is a bridge circuit, to which a third strain gauge disposed such that a detection direction is parallel to the longitudinal direction of the crank and a fourth strain gauge disposed such that a detection direction is perpendicular to the longitudinal direction of the crank are connected, detecting bending deformation y and tensile deformation z occurring in the crank are included.