Sources of error in determining countermovement lump height with the impulse method

A comprehensive error analysis was performed on the impulse method. To eval uate the potential errors, jump height was recalculated after altering one of the measurement or calculation techniquaes while leaving the others unch anged, and then comparing it to the reference jump height (best estimate of true jump height). Measurement techniques introduced the greatest error. L ow-pass filters with cutoff frequencies < 580 Hz led to systematic underest imations of jump height, <less than or equal to> 26%. Low sampling frequenc ies (<1,080 Hz) caused jump height to be underestimated by <less than or eq ual to> 4.4%. Computational methods introduced less error. Selecting takeof f too early by using an elevated threshold caused jump height to be overest imated by less than or equal to 1.5%. Other potential sources of computatio nal error: (a) duration of body weight averaging period; (b) method of inte gration; (c) gravity constant; (d) start of integration; (e) duration of of fset averaging period; and (f) sample duration, introduced < 1% error to th e calculated jump height. Employing the recommended guidelines presented in this study reduces total error to <less than or equal to> +/-0.76%. Failin g to follow the guidelines can lead to average errors as large as 26%.