1. A method of estimating stride speed corresponding to a subject element, the method comprising: acquiring an acceleration measurement using one or more accelerometers; determining an acceleration magnitude and a stride duration from the acceleration measurement using a processing system; generating a motion parameter metric with the processing system by using the stride duration and acceleration magnitude, wherein the motion parameter metric generated by at least performing an integration of a function of the acceleration magnitude; and estimating a first value which is function of stride speed with the processing system by using the motion parameter metric and outputting the estimated first value and/or a second value derived from the estimated first value.