Figure 6.

The dimensionless Groucho number across speed. The Groucho number increased with speed for in all subjects; however, the slopes were significantly greater for biological legs (bioL and UL) compared with legs with running-specific prostheses (AL and BL). Lower Groucho numbers indicate running with a ‘softer’ gait. The linear fit equations for Grouch number were bioL: Gr = 0.180x + 0.954, R² = 0.771, p < 0.001; UL: Gr = 0.170x + 0.920, R² = 0.593, p < 0.001; AL: Gr = 0.084x + 1.224, p = 0.001, R² = 0.227; BL: Gr = 0.064x + 1.124, R² = 0.339, p < 0.001. (a) Crosses with dashed line, bioL; filled circles with dashed line, UL. (b) Open circles with solid line, AL; crosses with dashed line, BL. (Online version in colour.)