A system for measuring the force of the feet of a user upon the support surface of an item of footwear for each foot at multiple locations has a plurality of sensors each predictably varying in resistance upon application of a force thereto. The sensors send signals reflective of the force to an A-D converter. The digitalized signals reflective of the resistance and in some cases deflection are sent to a receiver for storage in a memory and for further transmission to a computing device to compute and display the force at each of the multiple points. An accelerometer may also be combined proximate to or attached to the insert to supply signals reflective of the acceleration and which can be used to calculate and display other information including acceleration, speed and distance.