Fig. 3.
Ground reaction forces (GRF) during treadmill running in the Vaporfly shoes with intact (VFintact; red) and cut (VFcut; blue) carbon-fiber plates. The shaded bars represent ± 1 standard error. Force traces have been normalized to body weight (BW). (A) Average vertical (Fz) GRF traces, (B) Anterior−posterior (Fy) GRF traces. Grey shaded areas represent where traces are significantly different from each other (p < 0.05) as determined by spatial parametric mapping. (C) GRF vectors during stance phase. Each vector represents 1% of stance phase. Interestingly, around 60%−70% of stance phase, when GRF vectors appear to be the same, the VFcut (blue) is 1% behind the VFintact (red).