Fig. 3. Peak horizontal propulsive ground reaction force F_h⁺ and peak vertical force F_v increased with acceleration, while negative horizontal forces F_h^- decreased (A). Force is given as a proportion of body weight. The peak propulsive horizontal force, as a fraction of peak vertical force, increased with acceleration (B). The mean angle of the resultant ground reaction force (GFR) from vertical, averaged over the stride, increased with acceleration (C). Linear regressions (N=49) are shown for F_v (y=0.13x+1.69, r²=0.52, P<0.01), F_h⁺ (y=0.18x+0.207, r²=0.91, P<0.01), F_h^- (y=0.06x-0.27, r²=0.61, P<0.01), F_h/F_v (y=0.071x+0.132, r²=0.81, P<0.01) and ground reaction force angle (y=4.28x+1.03, r²=0.91, P<0.01).

Return to article