Fig. 4. Protraction duration as a function of speed. Values are means ± s.d. of individual horse mean data for lead and non-lead limbs (indicated by different symbols) and fore- and hindlimbs (red and blue, respectively) for the six horses for which complete data sets were available. Quadratic lines of best fit (P<0.001) are shown. These were determined for the population for fore- and hindlimbs separately using mean data. Coefficients: forelimb b₀=363.92, b₁=3.9561 and b₂=-0.3026; hindlimb b₀=288.88, b₁=13.141 and b₂=-0.5954.