Speed is frequency multiplied by how far each cycle carries you — its amplitude, or in gait terms, the stride length.Sprinters increase both: a faster leg-cycle frequency and a longer stride. Elite sprinters reach cadences above 4-5 steps/second with strides over two metres — two independent quantities, frequency and amplitude, multiplying into genuinely extreme speed.Keep this multiplication in mind: speed = frequency × amplitude. It will come back, almost unchanged, when we get to the piano.