Figure 4.

Average peak vertical ground reaction force (vGRF_peak) and (c,d) leg compression (ΔL) across speed. (a,b) Non-amputees (bioL) increased vGRF_peak at faster speeds. Subjects with a unilateral amputation increased vGRF_peak to a greater extent in their UL than in their AL. Subjects with bilateral amputations (BL) increased vGRF_peak with speed by a similar magnitude as unilateral AL, which was less than non-amputees and unilateral UL. (c,d) Non-amputees (bioL) did not change leg compression across velocity. Subjects with a unilateral amputation did not change leg compression in their UL, but increased leg compression with their AL at faster speeds. Subjects with bilateral amputations (BL) also increased leg compression at faster speeds. The linear fit equations for vGRF_peak were bioL: vGRF_peak = 0.144x + 2.40, R² = 0.615, p < 0.001; UL: vGRF_peak = 0.135x + 2.66, R² = 0.528, p < 0.001; AL: vGRF_peak = 0.094x + 2.42, R² = 0.341, p < 0.001; BL: vGRF_peak = 0.067x + 2.57, R² = 0.745, p < 0.001. The linear fit equations for ΔL were bioL: ΔL = 0 x + 0.196, R² = 0, p = 0.934; UL: ΔL = 0.003x + 0.226, R² = 0.014, p = 0.421; AL: ΔL = 0.009x + 0.172, R² = 0.206, p = 0.001; BL: ΔL = 0.012 x + 0.150, R² = 0.660, p < 0.001. (a,c) Crosses with dashed line, bioL; (a,c) circles with filled line, UL; (b,d) open circles with solid line, AL; crosses with solid line, BL. (Online version in colour.)