A method implementing an accelerometer for analyzing biomechanical parameters of a runner's stride. The method includes fastening a device (1) on the runner that has a triaxial accelerometer (17), a chronograph (16), a digital processor (19) and a display (11). The method measures a sequence of acceleration data in at least the vertical direction using the accelerometer, while the runner runs a certain distance (D) along a running course. During or at the end the running course, the processor calculates the biomechanical parameters of the stride, including lowering the center of gravity and/or the elevation (E) of the center of gravity and/or the sum of the lowering and of the elevation (E) and/or the vertical mechanical work of the center of gravity, based on the acceleration data, of the distance (D) and a period of time measured by the chronograph (16); and displays the parameters.