Therefore, the higher the ability to accelerate for a longer period with a greater amplitude, the better the performance. Short acceleration and limited amplitude will not bring about world class performance. – Gajer
The Ito and Suzuki study from the 1991 WC showed some interesting data with the amplitude of elite sprinters, but the real question about hip height is not just about the undulating body but how are world class performances made in practice? Who is addressing this directly? Good sprinters decelerate less in both horizontal speed and vertical forces, a relationship that often confuses people. The displacement of the center of mass from standing may be similar, but the eccentric drop at high speeds is less with the faster athletes as they tend to have higher stiffness values. Coach Shexnayder did a marvelous job showing oscillation in track and field and his presentation notes can be found here.