Fig. 6. Duty factor as a function of speed. Values are means + s.e.m. for forelimb level and hindlimb level and means – s.e.m. for forelimb incline and hindlimb incline (for clarity; N=6 throughout; indicated by different symbols) during level (0–2%) and incline (8–12%) galloping for the six horses. Quadratic lines of best fit (P<0.001) are shown. These were estimated for the population using mean data. Coefficients: forelimb level b₀=0.525, b₁=–0.031, b₂=0.001, r²=0.53; forelimb incline b₀=0.727, b₁=–0.066, b₂=0.002, r²=0.71; hindlimb level b₀=0.718, b₁=–0.063, b₂=0.002, r²=0.54; hindlimb incline b₀=0.667, b₁=–0.052, b₂=0.002, r²=0.69.